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PART 2: DRUGS AFFECTING
THE CENTRAL NERVOUS
SYSTEM
I: Analgesic drugs.
Overview:
Medications that relieve pain without causing loss of
consciousness are classified as analgesics. They are
also commonly to as painkillers. There are various classes
of analgesics, determined by their chemical structures and
mechanisms of action. Here we will focus on the opioid
analgesics, which are normally used to treat moderate to
severe pain. Often drugs from other chemical categories
are added to the opioid regimen as adjuvant analgesic
drugs.
Opioid agonists:
1.
2.
3.
4.
5.
6.
Codeine.
Fentanyl.
Meperidine (bethidine).
Methadone.
Morphine.
Oxycodone.
Partial agonist:
1. Buprenorphine.
2. Pentazocine.
Opioid antagonists
3. Naloxone.
4. Naltrexone.
Nonopioids
1. Paracetamol.
2. Tramadol.
Pain is most commonly defined as an unpleasant sensory and emotional experience associated with
either actual or potential tissue damage. It is a very personal and individual experience. Pain can be
defined as whatever the patient says it is, and it exists whenever the patient says it does.
GATE THEORY
Several theories attempt to explain pain transmission and pain relief. The most common and well
described is the gate theory. First, the tissue injury causes the release of several substances from
injured cells, such as bradykinin, histamine, potassium, prostaglandins, and serotonin. The release
of these pain-mediating chemicals initiates action potentials at the distal end of sensory nerve fibers
through receptors known as nociceptores.
These nerve impulses are conducted along sensory nerve fibers and activate pain receptors in the
dorsal horn of the spinal cord. It is here that the so called gates are located. These gates regulate
the flow of sensory nerve impulses. If impulses are stopped by a gate at this junction, no impulses
are transmitted to the higher centers of the brain. Conversely, if the gates permit a sufficient number
and intensity of action potentials to be conducted from the spinal cord to the cerebral cortex, the
sensation of pain is then felt.
The gate is innervated by nerve fibers that originate in the brain and modulate the pain sensation by
sending impulses to the gate, either keeping the gate closed or allowing it to open so that the brain is
stimulated and pain is sensed. The cells that control the gate have a threshold. Impulses that reach
these cells must rise above this threshold before an impulse is permitted to travel up to the brain.
The level of stimulus needed to produce a painful sensation is referred to as the pain threshold.
PAIN RECEPTORS:
There are three main receptors believed to be involved in pain.
-
The mu receptors.
Less important but still involved in pain sensations are the kappa and delta receptors.
Pain receptors are located in both the central nervous system (CNS) and various body tissues.
When these receptors are stimulated transmission of nerve impulses related to pain are inhibited.
Opioid drugs also react with these receptors and thus relieve pain, so these receptors also called
OPIOID RECEPTORS. All opioids act by binding to specific opioid receptors in the CNS to produce
effects that mimic the action of endogenous peptide neurotransmitters (for example, endorphins,
enkephalins, and dynorphins)
Figure below illustrate the four processes of nociception
 Endogenous analgesic substances (body’s pain killers):
The body is equipped with certain endogenous neurotransmitters known as enkephalins and
endorphins. These substances are produced within the body to fight pain and are considered the
body’s painkillers. Both are capable of bonding with opioid receptors and inhibiting the transmission
of pain impulses, in a manner similar to that of opioid analgesic drugs. These endogenous
substances are released whenever the body experiences pain.
 Adjuvant analgesic drugs.
The goals of pain management include reducing and controlling pain, improving body function and
quality of life.
Drugs from other chemical categories are often added to the opioid regimen as adjuvant drugs. This
adjuvant drug therapy may include NSAIDs, antidepressants, anticonvulsants and
corticosteroids. This approach allows the use of smaller dosages opioids. This reduces some of
the adverse effects that are seen with higher doses of opioids. It permits drugs with different
mechanisms of action to produce synergistic effects.
Pharmacology overview:
Opioid drugs:
Opioid analgesics are very strong pain relievers. They can be classified according to their chemical
structure or their action at specific receptors. Of the 20 different natural alkaloids available from the
opium poppy plant, only three are clinically useful: morphine, codeine, and papaverine. Of these,
only morphine and codeine are pain relievers; papaverine is a smooth muscle relaxant. Relatively
simple synthetic chemical modifications of these opium alakaloids are produced the three different
chemical classes of opioids: morphine-like drugs, meperidine-like drugs, and methadone-like
drugs.
 Mechanism of action and drug effects:
Opioid analgesics can be characterized according to their mechanism of action. They can be
agonists, agonists-antagonists (partial agonists), or antagonists (nonanalgesic).Agonists: binds to a
pain receptor in the brain and causes an analgesic response. Partial agonist: binds to a pain
receptor but causes a weaker pain response than a full agonist. Antagonist: binds to a pain
receptor but does not reduce pain signals, it reverses the effects of agonists and partial agonists at
the receptor site.
A. Agonists: morphine, meperidine (pethidine), methadone, fentanyl,codeine.
B. Partial agonists: pentazocine, nalbuphine, buprenorphine, butorphanol.
C. Antagonists: naloxone, naltrexone.
 Indications:

Main use: to alleviate moderate to severe pain
The degree to which pain is relieved or unwanted adverse effects occur depends on the
specific drug, the preceptors to which it binds, and its chemical structure.

Opioids are also used for:
 Cough center suppression
 Treatment of diarrhea
 Balanced anesthesia (use a combinations of drugs to produce anesthesia).
1- Morphine: They are often used to control postoperative and other types of pain. Because
morphine is available in injectable form,is often first-line analgesics in the immediate
postoperative setting. Morphine rapidly enters all body tissues, including the fetuses of
pregnant women, and should not be used for analgesia during labor.
2- Codeine: Codeine is a naturally occurring opioid that is a weak analgesic compared to
morphine. It should be used only for mild to moderate pain. Is the most commonly used
opioid for cough suppression, sometimes opioid-related cough suppressants have a
depressant effect on CNS and cause sedation. To avoid this problem, dextromethorphan a
nonopioid cough suppressant, is often given instead.
3- Fentanyl: used commonly in combination with anesthetics during surgery, it not only used to
relieve pain but also to maintain a balanced state of anesthesia. Used of fentanyl injection for
management of postoperative and procedural pain has become popular due to its rapid onset
and short duration.
4- Methadone: Methadone is a synthetic, orally effective opioid that induces less euphoria and
has a longer duration of action than morphine.can be used as analgesic and in the controlled
withdrawal of dependent abusers from heroin and morphine. Oral methadone is administered
as a substitute for the opioid of abuse, and the patient is then slowly weaned from
methadone. The withdrawal syndrome with methadone is milder but more protracted (days to
weeks) than that with other opioids.
5- Meperidine (Pethidine) it is used for acute pain. Can be administered orally or I.M.
Meperidine is very lipophilic and has anticholinergic effects, resulting in an increased
incidence of delirium as compared to other opioids.
6- Buprenorphine: partial agonists used for opioid detoxification
Use with extreme caution if:




Respiratory insufficiency
Elevated intracranial pressure
Sleep apnea
Is contraindicated in: severe asthma and known allergy
Adverse effects:





Euphoria
CNS depression leads to respiratory depression which is the most serious adverse effect
Nausea and vomiting
Urinary retention, Diaphoresis, flushing and constipation
Toxicity and management of overdose:
The opioid antagonists naloxone (IV) and naletroxone (PO) can reverse the adverse effects
induced by the opioid drug, such as respiratory depression. These drugs are used in the
management of both opioid overdose and opioid addiction.
When treating an opioid overdose or toxicity, the nurse must recognize the signs and symptoms of
withdrawal. A gradual dosage reduction after chronic opioid use, when possible, generally helps to
minimize the risk and severity of withdrawal symptoms.
Respiratory depression: Stimulation of the patient may be adequate to reverse mild
hypoventilation. Is this is unsuccessful, ventilator assistance using a bag and mask or endotracheal
intubation may be needed to support respiration. Administration of opioid anatagonists may also
necessary to reverse severe respiratory depression. Naloxone half-life is about 1 hour.

Interactions:
Co-administration of opioids with alcohol, antihistamines, barbiturates, benzodiazepine and other
CNS depressants can result in additive respiratory depression, seizures, and hypotension.
Other analgesics (Tamadol and Paracetamol):
A. Acetaminophen (paracetamol):
-Mechanism of action: it blocks peripheral pain impulses by inhibition of prostaglandin synthesis. It
also lowers febrile body temperatures by acting on hypothalamus.
-Indications: Is indicated for the treatment of mild to moderate pain and fever is the drug of choice
as antipyretic in children.
-Contraindications: known allergy, severe liver disease and G-6-PD
-Adverse effects: is generally well tolerated. Possible adverse effects include rash, nausea and
vomiting.
-Toxicity: the ingestion of large doses can cause hepatic necrosis. Acute hepatotoxicity can usually
reverse with acetylcysteine, where as long-term toxicity is more likely to be permanent. The
maximum daily dose is 4000mg and Acetylcysteine is more effective when given within 10 hours of
overdose. It is available as IV and OP dose.
B. Tramadol:
It is a centrally acting analgesic creates a weak bond to the mu receptors and inhibit reuptake of both
norepinephrine and serotonin. Is indicated for severe to moderately severe pain adverse effects are
include drowsiness, dizziness, headache, nausea, constipation and respiratory depression. Drug is
available as injection (IV, IM) and PO (tablet and capsules).
Analgesics: Nursing implications:
 Perform a thorough pain assessment, including pain intensity and character, onset, location,
description, precipitating and relieving factors, type, remedies, and other pain treatments
 Assessment of pain is now being considered a “fifth vital sign”
 Rate pain on a 0 to 10 or similar scale
 Be sure to medicate patients before the pain becomes severe so as to provide adequate
analgesia and pain control
 Pain management includes pharmacologic and nonpharmacologic approaches; be sure to
include other interventions as indicated
 Patients should not take other medications or over-the-counter preparations without checking
with their physician
 Instruct patients to notify physician for signs of allergic reaction or adverse effects
 Acetaminophen: patient education about the signs and symptoms of hepatotoxicity
(bleeding, loss of energy, fever, and sore throat). Maximum dose: 4 g.
 Tramadol: if dizziness, blurred vision, or drowsiness occurs, the nurse should assist the
patient to minimize the risk of fall and injury.
 Opioids: Ensure safety measures, such as keeping side rails up, to prevent injury. Withhold
dose and contact physician if there is a decline in the patient’s condition or if vital signs are
abnormal, especially if respiratory rate is less than 10 to 12 breaths/min. Constipation is a
common adverse effect and may be prevented with adequate fluid and
fiber intake

Monitor for Therapeutic Effects:
 Decreased complaints of pain
 Decreased severity of pain
 Increased periods of comfort
 Improved activities of daily living, appetite, and sense of well-being
 Decreased fever (acetaminophen)
II: Anesthetics.
Overview:
Anesthetics are drugs that cause complete or partial loss
of sensation. This state of reduced neurologic function is
called anesthesia.
Anesthesia is further classified as general or local.
General anesthesia normally involves complete loss of
consciousness, loss of body reflexes, elimination of pain
and other sensations throughout the entire body, and
skeletal and smooth muscle paralysis, including paralysis
of respiratory muscles. This loss of normal respiratory
function requires mechanical or manual ventilator support
to avoid brain damage and suffocation (death from
respiratory arrest). Local anesthesia does not involve
paralysis of respiratory function but does involve
elimination of pain sensation in the tissue innervated by
anesthetized nerves.
Pharmacology overview
1- General anesthetics:
-General anesthetics are drugs that induce general
anesthesia and are most commonly used to induce
anesthesia during surgical procedures.
-General anesthesia is achieved by the use of one or
more drugs. Often a synergistic combination of drugs is
used, which allows for smaller doses of each drug and
better control of the patient’s anesthetized state.
-Inhalational anesthetics are volatile liquids or gases
that are vaporized or mixed with oxygen to induce
anesthesia.
General anesthetics:inhaled




Nitrous oxide.
Halothane.
Isoflurane.
Sevoflurane.
General anesthetics:parenteral




Ketamine
Etomidate.
Propofol.
Thiopental.
Adjunctive anesthetic drugs




Benzodiazepines.
Antihistamines.
Opioids.
Barbiturates.anticholinergics
.
Neuromascular blocking drugs




Pancuronium.
Vecuronium.
Atracurium.
Succinylcholine.
Local anesthetics





Bupivacaine.
Lidocaine (Xylocaine)
mepivacaine
(Carbocaine)
procaine (Novocain)
tetracaine (Pontocaine)
-Parenteral anesthetics usually given IV and are used for induction and/or maintenance of general
anesthesia, induction of amnesia, and as adjuncts to inhalation anesthetic. The specific goal varies
with the drug.
In addition, there are also adjunct anesthetics. Adjunct drugs can be thought as “helper drugs”
when their use complements the use of any other drug(s) and are used simultaneously with general
anesthetics for anesthesia induction, sedation, reduction of anxiety, and amnesia. The simultaneous
use of both general anesthetics and adjuncts is called balanced anesthesia.
Adjuncts:





Neuromuscular blocking agents.
Sedative hypnotics or anxiolytics.
 Propofol, benzodiazepines, barbiturates, hydroxyzine and promethazine.
Opioid analgesics.
Anticholinergics (atropine).
Antiemetics (ondansetron).
Note that propofol can be used as a general anesthetic and/or sedative-hypnotic, depending on the
dose.
 Mechanism of action and drug effects:
The drugs vary widely in their chemical structures, and their mechanism of action is not easily
explained by a structure-receptor relationship. The concentrations of various anesthetics required to
produce a given state of anesthesia also differ greatly. Fat-soluble drugs are stronger anesthetics
than water-soluble drugs. Nerve cell membranes have high lipid content, as does the blood-brain
barrier. Lipid-soluble anesthetic drugs can therefore easily cross the blood-brain barrier to
concentrate in nerve cell membranes.
The overall effect of general anesthetics is a progressive reduction of sensory and motor CNS
functions. The degree and speed of this process varies with the anesthetics and adjuncts used along
with their dosages and routes of administration. General anesthesia initially produces a loss of
the senses of sight, touch, taste, smell, and hearing, along with loss of consciousness.
Cardiac and pulmonary functions are usually the last to be interrupted; these are the
classical “stages” of anesthesia. Again, mechanical ventilator support is usually necessary. In
more extensive surgical procedures, especially those involving the heart, pharmacologic cardiac
support may also be required.
 Adverse Effects:
 Vary according to dosage and drug used
 Sites primarily affected
o Heart, peripheral circulation, liver, kidneys, respiratory tract
 Myocardial depression is commonly seen
 Malignant hyperthermia is an uncommon, but potentially fatal.
o Occurs during or after general anesthesia or use of the NMBC succinylcholine
o Sudden elevation in body temperature (greater than 104° F)
o Tachypnea, tachycardia, muscle rigidity
o Life-threatening emergency
o Treated with dantrolene (skeletal muscle relaxant)
 Drug profiles:
The dose of any anesthetic depends on the complexity of the surgical procedure to be
performed and the physical characteristics of the patient. With regard to pharmacokinetics,
all of the general anesthetics have a rapid onset of action along with rapid elimination upon
discontinuation. Anesthesia is maintained intraoperatively by continuous administration of
the drug.
Isoflurane: Is fluorinated ether that is a chemical isomer of the older fluorinated ether enflurane. It
has a more rapid onset of action, causes less cardiovascular depression, and has a little or no
associated toxicity.
Sevoflurane: Is the newest fluorinated ether and is now widely used. Its pharmacokinetics, with
rapid onset and rapid elimination, make it especially useful in outpatient surgery settings. It is also
nonirritating to the airway, which greatly facilitates induction of an unconscious state, especially in
pediatric patients.
Ketamine: It is a unique drug with multiple properties. Given IV, it can be used for both general
anesthesia and moderate sedation. This drug is highly lipid soluble and penetrates the blood-brain
barrier rapidly, which results in a rapid onset of action. It has a low incidence of reduction of
cardiovascular, respiratory, and bowel function. Adverse effects include hallucinations.
Propofol (Diprivan): Is a parentral general anesthetic used for the induction and maintenance of
general anesthesia and also for sedation for mechanical ventilation in ICU settings. In lower doses it
can be used as a sedative-hypnotic for moderate sedation. Some states allow nurses to administer
propofol as part of a moderate sedation protocol. Is also typically well tolerated, producing few
undesirable effects.
 Moderate Sedation:
 It also called conscious sedation, and procedural sedation. It’s anesthesia that does not
necessarily cause complete loss of consciousness and does not normally cause respiratory
arrest. This technique uses combination of several drugs from different groups. Drugs may
be given by IV, IM, spinal or oral routes. The net effect is a type of anesthesia that allows
the patient to relax, yet still maintain his or her own open airway, as well as respond to
verbal commands. Used for diagnostic procedures and minor surgical procedures that do
not require deep anesthesia
2- Local anesthetics:
Local anesthetics are the second major class of anesthetics. They reduce pain sensations at the
level of peripheral nerves. They also called regional anesthetics because they render a specific
portion of the body insensitive to pain. They do this by interfering with nerve transmission in specific
areas of the body, blocking nerve conduction only in the area in which they are applied without
causing loss of consciousness. They are most commonly used in clinical settings in which loss of
consciousness is undesirable or unnecessary. These include childbirth, dental procedures, and
diagnostic procedures.
 Types of local anesthesia:
1-Central:
Spinal or intraspinal anesthesia: Anesthesia drugs are injected into the area near the spinal cord
within the vertebral column. Intraspinal anesthesia is commonly accomplished by one of two injection
techniques: intrathecal and epidural.
Intrathecal anesthesia: involves injection of anesthesia into the subarachnoid space.
Epidural anesthesia: involves injection of anesthesia via a small catheter into the epidural space
without puncturing the dura.
2-Peripheral:
Infilteration: small amounts of anesthetic solution are injected into the tissue that surrounds the
operative site.
Nerve block: anesthetic solution is injected at the site where the nerve innervates a specific are
SUCH AS A tissue.
Topical anesthesia: the anesthetic drug is applied directly onto the surface of the skin, eye,
or any mucous membrane to relieve pain or prevent it from being sensed.
 Mechanism of action and drug effects:
Local anesthetics work by rendering a specific portion of the body insensitive to pain by interfering
with nerve transmission in that area. They block the generation and conduction of impulses through
all types of nerve fibers by blocking the movement of certain ions important to this process.
 Adverse effects;
Possible systemic effects of the administration of local anesthetics include effects on circulatory and
respiratory function. The systemic adverse effects depend on where and how the drug is
administered. Such adverse effects are somewhat unlikely unless large quantities of a drug that are
injected.
 Drug profiles:
Lidocaine: is one of the most commonly used local anesthetics. It is available in several strengths,
both alone and in different concentrations with epinephrine, and is used for both infiltration and nerve
block anesthesia. Lidocaine is also available in topical form. Parenteral lidocaine is also used to treat
certain cardiac dysrhythmias.
3- Neuromuascular blocking drugs (NMBDs):
These drugs prevent nerve transmission in skeletal and smooth muscles, leading to paralysis. They
are often used as adjuncts with general anesthetics. NMBDs also paralyze respiratory muscles, so
mechanical ventilation is required to prevent brain damage or death by suffocation.
 Mechanism of action:
They are classified into two groups based on mechanism of action: depolarizing and
nondepolarizing. Depolarizing work similarly to the neurotransmitter acetylcholine, they are
competitive agonists. Nondepolarizing also bind to acetylcholine receptors at neuromuscular
receptors at neuromuscular junction, and they block the usual action of acetylcholine, therefore
these drugs are competitive antagonists of acetylcholine.
NMBDs:
Depolarizing: succinylcholine.
Nondepolarizing:
Short acting: mivacurium.
Intermerdiate-acting drugs: atracurium, rocuronium and vecuronium.
Long-acting drugs: dexacurium, pancuronium and tubocurarine.
 Indications:




Main use: maintaining controlled ventilation during surgical procedures
Endotracheal intubation (short-acting)
To reduce muscle contraction in an area that needs surgery
Diagnostic drugs for myasthenia gravis
 Adverse effects:
 Few when used appropriately
 May cause:
 Hypotension (blockade of autonomic ganglia)
 Tachycardia (blockade of muscarinic receptors)
 Hypotension (release of histamine)
 Drug profiles:
Succinylcholine: Is the only currently available drug in the depolarizing subclass of NMBDs. This
drug stimulates the same neuron as Ach and produces the same physiological responses initially.
Succinylcholine is metabolized more slowly. Because of this slower metabolism, repolarizing cannot
occur. As long as sufficient concentrations are present, the muscles lose its ability to contract, and
flaccid muscle paralysis results. Because of its quick onset of action (less than 1 min),
succinylcholine is most commonly used to facilitate endotracheal intubation.
Pancuronium: Is a long-acting nondepolarizing NMBD. It’s used as an adjunct to general
anesthesia to facilitate endotracheal intubation and to provide skeletal muscle relaxation during
surgery or mechanical ventilation. Its most commonly employed for long surgical procedures that
require prolonged muscle paralysis.
Vancuronium: Is an intermediate-acting nondepolarizing NMBD. It is used as an adjunct to general
anesthesia to facilitate tracheal intubation and to provide skeletal muscle relaxation during surgery or
mechanical ventilation, and is one of the most commonly used NMBDs. Long-term used in the ICU
setting has resulted in prolonged paralysis and subsequent difficulty in weaning.
 Nursing implications:
 Always assess past history of surgeries and response to anesthesia
 Assessment is vital during preoperative, intraoperative, and postoperative phases
 Vital signs
 Baseline lab work, ECG
 Oxygen saturation
 ABCs (airway, breathing, circulation)
 Monitor all body systems
 Nursing considerations during the perioperative phase include:
 Preoperative phase
 Intraoperative phase
 Postoperative phase
 Each phase has its own complex and very specific nursing actions
 Watch for sudden elevations in body temperature, which may indicate malignant
hyperthermia
 During recovery, monitor for cardiovascular depression, respiratory depression, and
complications of anesthesia
 Implement safety measures during recovery, especially if motor or sensory loss occurs
because of local anesthesia
 Reorient patient to his or her surroundings
 Teach the patient about postoperative turning, coughing, deep breathing
III. Antiepileptic drugs
 Traditional antiepileptic
drugs:
Disease overview:
- Phenobarbital.
Epilepsy:
- Phenytoin .
Epilepsy is the most common chronic neurologic illness. It
results from excessive electrical activity of neurons
located in the superficial area of the brain known as the
cerebral cortex. The terms convulsive, seizure, and
epilepsy are often used interchangeably, but they do not
have the same meaning.
-Benzodiazepines: diazepam,
clonazepam
A seizure is a brief episode of abnormal electrical active
in the nerve cells of the brain, which may or may not lead
to a convulsion.
A convulsion is a more severe seizure characterized by
involuntary spasmodic contractions of any or all voluntary
muscles throughout the body.
- Carbamazepine (Tegretol),
Oxcarbazepine (Trileptal).
- Valproic acid.
 Newer antiepileptic
drugs:




Gabapentin (neurontin).
Lamotrigine (Lamictal),
Levetiracetam (Keppra).
Topiramate (Topamax).
Epilepsy is chronic, recurrent pattern of seizures. These
excessive electrical discharges can often be detected by an electroencephalogram (EEG), which is
commonly obtained to help diagnose epilepsy.
Because up to 50% of patients with epilepsy have normal EEGs, a careful history is important for
accurate diagnosis. Other applicable diagnostic tests include skull radiography, computed
tomography, and magnetic resonance imaging.
-Primary epilepsy: Epilepsy without an identifiable cause is known as or idiopathic epilepsy.
-Secondary epilepsy: Epilepsy has a distinct cause, such as trauma, infection, cerebrovascular
disorder, or other illness, also some drugs can cause epilepsy.
- Febrile seizure occurs in children aged 6 months to 5 years and by definition be caused by fever.
Children usually outgrow the tendency to have such seizures, and thus these seizures do not
constitute a chronic illness.
Status epilepticus: In status epilepticus, two or more seizures occur without recovery of full
consciousness in between episodes. These may be focal or primary generalized, convulsive or
nonconvulsive. Status epilepticus is life threatening and requires emergency treatment usually
consisting of administration of a fast-acting medication such as a benzodiazepine, followed by a
slower-acting medication such as phenytoin.
Pharmacology overview:
 Antiepileptic drugs:
The goal of antiepileptic drug therapy is to control or prevent seizures while maintaining a
reasonable quality of life. Many antiepileptic drugs have adverse effects. In most cases, the
therapeutic goal is to maximally reduce the incidence of seizures while minimizing drug-induced
toxicity.
A number of antiepileptic drugs are available. Sometimes, a combination of drugs must be given to
control the disorder. Generally, single-drug therapy must fail before two-drug or multidrug therapy is
attempted. Antiepileptic drugs should never be stopped abruptly unless a severe adverse effect
occurs.
Therapeutic drug monitoring of serum drug concentrations provides a useful guideline in assessing
the effectiveness of therapy. Maintaining serum drug levels within therapeutic ranges therapeutic
ranges helps not only to control seizures but also to reduce adverse effects. However, each patient
should be monitored individually, and the dosages adjusted based on the individual case.
Successful control of a seizure disorder hinges on selection of the appropriate drug class and drug
dosage, avoidance of drug toxicity, and patient compliance with the treatment regimen.
 Mechanism of action:
As with many classes of drugs, the exact mechanism of action of the antiepileptic drugs is not known
with certainty. However, strong evidence indicates that they alter the movement of sodium,
potassium, calcium, and magnesium. The changes in the movement of these ions induced by
antiepileptic drugs result in more stabilized and less excitable cell membranes.
Regardless of mechanism, however, the overall effect is that antiepileptics stabilize neurons
and keep them from becoming hyper excited and generating excessive nerve impulses to
adjacent neurons. Some work by enhancing the effects of the inhibitory neurotransmitter
gamma-aminobutyric acid (GABA).
 Indications:
Antiepileptic drugs are chiefly used for the long-term maintenance treatment of epilepsy. However,
they are also useful for the acute treatment of convulsions and status epilepticus. In these cases the
therapy is typically diazepam, which is considered by many to be the drug of choice. Once status
epilepticus is controlled, long-term drug therapy is begun with other drugs for the prevention of future
seizures.
 Drug profiles:
A. Benzodiazepines
Benzodiazepines bind to GABA inhibitory receptors to reduce firing rate. Most benzodiazepines are
reserved for emergency or acute seizure treatment due to tolerance. However, clonazepam and clobazam
may be prescribed as adjunctive therapy for particular types of seizures. Diazepam is also available for
rectal administration when oral administration is not possible.
B. Carbamazepine (Tegretol):
-
-
It was marketed in the late 1960s for the treatment of epilepsy in adults after its efficacy and
safety for the treatment of trigeminal neuralgia was proved.
Carbamazepine blocks sodium channels, thereby inhibiting the generation of repetitive action
potentials in the epileptic focus and preventing their spread.
Carbamazepine is effective for treatment of focal seizures and, additionally generalized
tonic–clonic seizures, trigeminal neuralgia, and bipolar disorder.
Carbamazepine is associated with autoinduction of hepatic enzymes. Autoinduction is a
process in which, over time, a drug stimulates the production of enzymes that enhance its
own metabolism, which leads to lower than expected drug concentrations.
Hyponatremia may be noted in some patients, especially the elderly, and may necessitate a
change in medication.
C.Gabapentin:
-
-
Gabapentin is a chemical analogue of GABA, a major neurotransmitter that inhibits brain
activity. It is indicated as an adjunct drug for the treatment of partial seizures and for
prophylaxis of partial seizures. Its precise mechanism of action is not known.
Also gabapentin is effective as a single-drug therapy for the new-onset epilepsy.
It is also commonly used to treat neuropathic pain.
Adverse effects include CNS and GI symptoms.
D.Phenobarbital:
-
Phenobarbital is used primarily in the treatment of status epilepticus when other agents fail.
Is an effective prophylactic drug for the control of febrile seizures
In developing countries, however, oral Phenobarbital is often the drug of choice for routine
seizure prophylaxis because of its lower cost compared with the newer drugs.
Phenobarnital associated with physical dependence and withdrawal syndrome.
The most common adverse effect is sedation.
Contraindications include known drug allergy, liver or kidney impairment, and respiratory
illness.
Phenobarbital interacts with many drugs because it is a major liver enzyme inducer.
Phanobarbital is available in oral and injectable forms.
E.Phenytoin:
-
-
Phenytoin is primarily indicated for the management of tonic-clonic and partial seizures.
Contraindications include known drug allergy and heart conditions that involve bradycardia.
The most common adverse effects are lethargy, abnormal movements, and mental
confusion.
Long-term phenytoin therapy can cause gingival hyperplasia, acne, and hirsutisim.
Phenytoin can interact with other medications for two reasons. First, it is highly bound to
plasma proteins and competes with other highly protein-bound medications for binding sites.
Second, it induces hepatic enzymes.
Phenytoin is generally well tolerated, highly effective, and relatively inexpensive.
It can also be given intravenously if needed. Most often, however, phenytoin is taken orally.
Valproic acid:
-
Valproic acid is used primarily in the treatment of generalized seizures. It has also been
shown to be effective in controlling partial seizures.
Contraindications include known drug allergy, liver impairment, and urea cycle disorders.
Common adverse effects include drowsiness; nausea, vomiting, and other GI disturbances;
tremor; weight gain; and transient hair loss.
The most serious adverse effects are hepatotoxicity and pancreatitis.
The main reason for the drug interactions with valproic acid are protein binding and liver
metabolism. The drug is available in both oral and injectable.
 Nursing Implications:
 Oral drugs
 Take regularly, same time each day with meals to reduce GI upset
 Do not crush, chew, or open extended-release forms
 Intravenous forms
 Follow manufacturer’s recommendations for IV delivery—usually given slowly and
monitor vital signs during administration
 Avoid extravasation of fluids
 Teach patients to keep a journal to monitor:
 Response to AED (Antiepileptic drugs)
 Seizure occurrence and descriptions
 Adverse effects
 Instruct patients to wear a medical alert tag or ID and AEDs should not be discontinued
abruptly
 Driving may be impaired until drug levels stabilize
 Teach patients that therapy is long term and possibly lifelong (not a cure)
 Monitor for therapeutic effects: Decreased or absent seizure activity
 Monitor for adverse effects
 Mental status changes, mood changes, changes in level of consciousness.
 Eye problems, visual disorders, Sore throat, fever (blood dyscrasias may occur
with hydantoins)
 Many others
Benzodiazepines:
IV. Sedatives and hypnotics.
Overview:
Drugs that have a calming effect or that depress the CNS
are referred to as sedatives and hypnotics.
Anxiolytic: drug used to depress the central nervous
system (CNS); prevents the signs and symptoms of
anxiety.
Sedatives reduce nervousness, excitability, and irritability
without causing sleep.
Hypnotics cause sleep and have a much more potent
effect on the CNS than do sedatives.
Many drugs can act in the body as either a sedative or a
hypnotic, depending on dose and patient responsiveness,
and for this reason are called sedative-hypnotics.


-Long acting:
Diazepam, lorazepam
-Short acting:
Alprazolam, Midazolam
Nonbenzodiazepines:


Zaleplon.
Zolpidem.
Ramelteon.
Barbiturates:




Ultrashort acting: thiopental.
Short acting: pentobarbital,
secobarbital.
Intermediate acting:
butabarbital.
Long acting: Phenobarbital.
Sedative-hypnotics can be classified chemically into three main groups: barbiturates,
benzodiazepines, and miscellaneous drugs.
1- Anxiety:
Anxiety is the unpleasant state of mind chiefly characterized by a sense of dread and fear.
Persistent anxiety is divided clinically into several distinct disorders, including the following:






Obsessive-compulsive disorder.
Post-traumatic stress disorder.
Generalized anxiety disorder.
Panic disorder with or without agoraphobia.
Social phobia.
Simple phobia.
Anxiety is a normal physiologic emotion. Anxiety may occur as a result of a wide range of medical
illness (e.g., cardiovascular or pulmonary disease, hypothyroidisim and hypoglycemia).
-
1- Anxiolytic drugs:
Benzodiazepines.
Buspirone.
Beta-blockers.
Antideprassants.
1- Benzodiazepines:
Diazepam, lorazepam, midozolam.
 Mechanism of action and drug effects:
All anxiolytic drugs decrease anxiety by reducing overactivity in the CNS.
Benzodiazepines seem to exert their effects by depressing activity in the areas of the brain called the
brainstem and the limbic system.
Benzodiazepines are believed to accomplish this by increasing the action of gammaaminobutyric acid, which is an inhibitory neurotransmitter in the brain that inhibits nerve
transmission in the CNS.
 Indications:
Benzodiazepines have a variety of therapeutic applications. They are commonly used for:
-
-
-
-
Anxiety relief.
Sleep disorders--- Commonly prescribed benzodiazepines for sleep disorders include
intermediate-acting temazepam and short-acting triazolam
Skeletal muscle relaxation-----Diazepam is useful in the treatment of skeletal muscle
spasms
Treatment of seizure disorders----Clonazepam is occasionally used as an adjunctive
therapy for certain types of seizures, whereas lorazepam and diazepam are the drugs of
choice in terminating status epilepticus
Amnesia---The shorter-acting agents are often employed as premedication for anxietyprovoking and unpleasant procedures, such as endoscopy, dental procedures, and
angioplasty. Midazolam is a benzodiazepine used to facilitate amnesia while causing
sedation prior to anesthesia.
Finally, benzodiazepines receptors in the CNS are in the same area as those that play a role
in alcohol addiction. Therefore, some benzodiazepines are used in the treatment and
prevention of the symptoms of alcohol withdrawal--- chlordiazepoxide, clorazepate,
diazepam, lorazepam, and oxazepam are useful in the acute treatment of alcohol
withdrawal and reduce the risk of withdrawal-related seizures.
When these drugs are used to treat insomnia, it is generally recommended that they be used
in short term to avoid dependency.
 Contraindications:
Contraindications to the use of benzodiazepines are known drug allergy, narrow-angle glaucoma,
and pregnancy.
 Adverse effects:
The adverse effects are associated with their use are usually mild and primarily involve the CNS.
The more commonly reported undesirable effects are headache, drowsiness, paradoxical excitement
or nervousness, dizziness or vertigo, cognitive impairment, and lethargy. Also they can create a
significant fall hazard in elderly patient.
 Toxicity and management of overdose:



Somnolence, Confusion, Coma, and Diminished reflexes
Do not cause hypotension and respiratory depression unless taken with other CNS
depressants
Treatment: symptomatic and supportive. Use Flumazenil as an antidote.
 Drug profiles:
Diazepam:
Diazepam was the first clinically available benzodiazepine drug. It has varied uses, including
treatment of anxiety, procedural sedation and anesthesia adjunct, anticonvulsant therapy, and
skeletal muscle relaxation. It is available in oral, rectal and injectable forms.
2- Buspirone:
Buspirone is an attempt to produce an anxiolytic drug without adverse effects. It appears to
have no sedative action or risk of dependence; its only adverse effects appear to be
occasional nausea and headache.
3- Antidepressants:
-
Will be discussed in the next chapter.
2- Insomnia:
-
Insomnia can, however, cause feelings of anxiety, inability to concentrate and general
debility.
It is necessary to find out if there is some reason for failing to sleep. These
reasons may include:
Anxiety and stress.
Depression.
Physical illness.
Pain.
physiology of sleep:
Sleep is defined as a transient, reversible, and periodic state of rest in which there is a decrease in
physical activity and consciousness. Sleep research involves study of the patterns of sleep, or what
is sometimes referred to as sleep architecture. The architecture of sleep consists of two basic
elements that occur cyclically: rapid eye movement (REM) sleep and non-rapid eye movement
(non-REM) sleep. Prolonged sedative-hypnotic use may reduce the cumulative amount of REM
sleep; this is known as REM interference. This can result in daytime fatigue. On discontinuance of a
sedative-hypnotic drug, REM rebound can occur in which the patient has an abnormally large
amount of REM sleep, often leading to frequent and vivid dreams.
Pharmacology overview:
1- Benzodiazepines.
Benzodiazepines (BDZ) are classified as either sedatives-hypnotics or anxiolytics depending on their
primary usage. However, any of these drugs can function along a continuum as a sedative and/or
hypnotic and/or anxiolytic depending on the dosage and patient sensitivity to drug action.
2- Nonbenzodiazepines.
Zaleplon and zolpidem.
Benzodiazepines used to be the most commonly prescribed sedative-hypnotic drugs; however, the
nonbenzodiazepine drugs are now the most frequently used.
There are five benzodiazepines commonly used as sedative-hypnotic drugs. In addition, there are
several miscellaneous drugs that are used primarily as hypnotics. They function much like
benzodiazepines but are chemically distinct from them.
Zolpidem: It is also a short-acting hypnotic. It’s has a lower incidence of daytime sleepiness
compared to benzodiazepines.
3- Ramelteon:
-
Is the newest prescription hypnotic.
This drug is structurally similar to the hormone melatonin, which is believed to regulate daynight sleep cycles in the body.
Ramelteon works as agonist at the body’s melatonin receptors in the CNS.
Is used as hypnotic, its lack dependency effect.
It potentially has a shorter duration of action than other hypnotics and is therefore indicated
primarily for patients who have difficulty with sleep onset rather than sleep maintenance.
Its use is contraindicated in cases of severe liver disease.
4- Barbiturates:
They were first introduced into clinical use in 1903 and were the standard drugs for treating insomnia
and producing sedation. Barbiturates can produce many unwanted adverse effects. They are habit
forming and have a low therapeutic index. Barbiturates can be classified into four groups based on
their onset and duration of action.
 Mechanism of action and drug effects:
They act primarily on the brainstem in an area called the reticular formation. Their sedative and
hypnotic effects are dose related, and they act by reducing the nerve impulses traveling to the
area of the brain called the cerebral cortex. Their ability to inhibit nerve impulse transmission is in
part due to their ability to potentiate the action of inhibitory neurotransmitter GABA.
 Indications:
 Ultra short-acting: thiopental Anesthesia for short surgical procedures, anesthesia
induction, and control of convulsions.
 Short-acting and intermediate Sedation/sleep induction and control of convulsive
conditions
 Long-acting: Phenobarbital. Sleep induction, epileptic seizure prophylaxis
 Contraindications:
Contraindications to barbiturate include known drug allergy, significant respiratory difficulties,
pregnancy and severe kidney or liver disease.
 Adverse effects:
They are enzyme inducers, they stimulate the action of enzymes in the liver for the metabolism of
many drugs, and this shortens the duration of action of many drugs.
Body System




CNS
Respiratory
GI
Other
Adverse Effects
Drowsiness, lethargy, vertigo, mental depression.
Respiratory depression, apnea, bronchospasms, cough.
Nausea, vomiting, diarrhea, constipation
Agranulocytosis, hypotension, Stevens-Johnson syndrome
5- Antihistamines like promethazine.
 Nursing implications:
 Give hypnotics 30 to 60 minutes before bedtime for maximum effectiveness in inducing sleep
(depends on drug’s onset)
 Most benzodiazepines cause REM rebound and a tired feeling the next day; use with caution
in the elderly
 Instruct patients to avoid alcohol and other CNS depressants
 Check with physician before taking any other medications, including over-the-counter
medications
 Rebound insomnia may occur for a few nights after a 3- to 4-week regimen has been
discontinued
 Safety is important:
-
Keep side rails up, or use bed alarms and keep call light reach.
Assist patient with ambulation (especially the elderly)
V: Antipsychotics and
antidepressants.
ANTIDEPRESSANTS:
Selective serotonine reuptake
inhibitors SSRIs





A. Antidepressants:
Overview:
Depression: affective disorder in which a person
experiences sadness that is much more severe and
longer lasting than is warranted by the event that seems
to have precipitated it, with a more intense mood; the
condition may not even be traceable to a specific event or
stressor.
The etiology of depression is not known but there is
evidence that a major factor is a reduction in the amount
of neurotransmitters such as serotonin 5-HT or
norepinephrine at the junctions between neurons in the
brain.
Antidepressants are the pharmacologic treatment of
choice for major depressive disorders. Many of the drugs
currently used to treat effective disorders increase the
levels of serotonin, dopamine, and norepinephrine
concentrations in the CNS. This treatment is based on the
belief that alterations in the levels of these
neurotransmitters are responsible for causing depression.
Citalopram.
Escitalopram.
Fluoxetine.
Paroxetine.
Sertraline.
Serotonine norepinephrine
reuptake inhibitors SNRIs.


Duloxetine.
Venlafaxine.
Tricyclic antidepressant TCA



Amitriptyline.
Clomipramine.
Imipramine.
Tetracyclic antidepressants

Mirtazapine.
Monoamine oxidase inhibitors
MAOIs
Recent research data indicate that early and aggressive antidepressant treatment increases the
chances for full remission. The first 6-8 weeks of therapy constitute the acute phase. The primary
goals during this time are to obtain a response to drug therapy and to improve the patient’s
symptoms.
It is currently recommended that antidepressant drug therapy be maintained at the effective dose for
an additional 8-14 months after remission of depressive symptoms. Therapeutic response is
measured primarily by subjective patient feedback.
A therapeutic non-response to antidepressant drug therapy is defined as failure to respond to at
least 6 weeks of therapy with adequate drug dosages. Therefore, dosage optimization, which
involves careful upward titration of medication dose for several weeks, is recommended before
concluding that a given drug is ineffective in treating a particular patient.
Pharmacology overview:
-
Older generation: tricyclic antidepressant TCA drugs, monoamine oxidase inhibitors MAOIs
Newer generation: selective serotonine reuptake inhibitorsSSRIs, serotonine
norepinephrine reuptake inhibitors SNRIs, miscellaneous.
1- Monoamine oxidase inhibitors MAOIs:
-
Isocarboxazid, phenelzine, and tranylcypromine.
They are now rarely used. This is partly because newer, safer drugs are now available
A serious disadvantage to MAOI use is their potential to cause a hypertensive crisis when
taken with a substance containing tyramine, which is found in many common foods and
beverages.
2- Tricyclic antidepressants:
 Amitriptyline.
 Clomipramine.
 Imipramine.
-
Now TCAs are generally considered second-line drug therapy for patients for whom the
newer drugs are ineffective or as adjunct therapy with newer drugs.
TCAs are so named because of their characteristic three-ring chemical stricture.
 Mechanism of action:
TCAs are believed to work by correcting imbalance in the neurotransmitter concentrations of
serotonin and norepinephrine at the nerve endings in the CNS (the biogenic amine hypothesis).
This is accomplished by blocking presynaptic reuptake of the neurotransmitters, which makes them
available for transmission of nerve impulses to adjacent neurons in the brain. Some also believe that
these drugs may help regulate malfunctioning neurons (the dysregulation therapy).




Indications
Originally used to treat depression currently,
TCAs are most commonly used to treat neuropathic pain syndromes and insomnia.
Some of the TCAs have additional specific indications. For example, imipramine is used as
an adjunct in the treatment of childhood enuresis (bedwetting), and clomipramine is useful in
treatment of obsessive-compulsive disorder.
 Contraindications
Contraindications include known drug allergy, and pregnancy. TCAs are also not recommended in
patient with any acute or chronic cardiac problems or history of seizures, because both conditions
are associated with a greater likelihood of death upon TCA overdose.
 Adverse effects: The most common adverse effects have being constipation and urinary
retention. Also they can lead to disturbances in cardiac conduction, hypotension, and sexual
dysfunction.
3- Tetracyclic antidepressants:
 Maprotiline
 Mirtazapine.
 Drug profile:
 Mirtazapine (remeron):
-
Associated with sedation due to histamine H1 receptor activity.
Dosed once daily at bedtime.
Increase appetite.
4- Selective serotonin reuptake inhibitors SSRIs
 Citalopram, Escitalopram, Fluoxetine, Paroxetine, Sertraline.
5- Serotonin norepinephrine reuptake inhibitors SNRIs
 Duloxetine, Venlafaxine.
They are associated significantly fewer and less severe systemic adverse effects, compare with
older-generation.
 Mechanism of action:
They inhibit the serotonin reuptake; this seems the primary mechanism of action of the SSRIs. Other
drugs have weak effects on norepinephrine and dopamine reuptake and called SNRIs. Patients
should be educated that antidepressant drugs commonly must be taken for several weeks before full
therapeutic effects are realized. This requires some patience and faithful dosing on the part of
patients.
 Indications:
- Depression is their primary indication.
- Have shown benefit in treating a variety of other mental and physical disorders (bipolar
disorder, eating disorders, and obsessive-compulsive disorder.…. Etc)
 Adverse effects: Some of the most common adverse effects are insomnia, weight gain, and
sexual dysfunction.
 Interactions:
The newer-generation antidepressants are highly bound to albumin. When given with other drugs
that are also highly protein bound (e.g., warfarin and phenytoin), they compete for binding sites for
binding sites on the surface of albumin. This results in a more free unbound drug and therefore a
more pronounced drug effect. Some of these drugs may also inhibit cyt P-450 enzymes, inhibition of
these enzymes results in higher levels of drugs that metabolized by this system.
B. Antipsychotic drugs:
Overview:
Mental disorders are now thought to be caused by some
inherent dysfunction within the brain that leads to abnormal
thought processes and responses. Psychosis is a severe
mental disorder that often impairs mental function to the point
of causing significant disability in performing the activities of
daily living. A hallmark of psychosis is a loss of contact with
reality. The primary psychotic disorders are schizophrenia and
depressive and drug –induced psychoses.
The dopamine hypothesis of psychotic illness grows out of
the observation that psychotic patients often have excessive
dopaminergic activity in the brain. Drug therapy is therefore
aimed at reducing this activity.
Because no diagnostic laboratory tests are available, patient
assessment and response must be carefully evaluated to
determine the basis of a particular problem. Selected disorders
are discussed here.
Schizophrenia, the most common type of psychosis, can be
very debilitating and prevents affected individuals from
functioning in society. Characteristics of schizophrenia include
hallucinations, paranoia, delusions, speech abnormalities, and
affective problems. This disorder, which seems to have a very
Antipsychotics:

-
Older generation:
Thioridazine.
Trifluoperazine.
Chlorpromazine.
Haloperidol.

-
Newer generation:
Clozapine.
Olanzapine.
Risperidone.
Aripiprazole.
Drugs used to treat mania and
bipolar disorder




Lithium
Carbamazepine.
Lamotrigine.
Valproic acid.
Mania, with its associated bipolar illness (i.e., manicdepressive illness), is characterized by periods
of extreme overactivity and excitement.
Bipolar disorder involves extremes of depression alternating with hyperactivity and excitement.
This condition may reflect a biochemical imbalance followed by overcompensation on the part of
neurons and their inability to re-establish stability.
Pharmacology overview:
Antipsychotics:
There are few overall differences between antipsychotics in terms of mechanism of action.
Therefore, selection of an antipsychotic is based primarily on the patient’s tolerance and the need to
minimize adverse effects, it should also stressed that antipsychotic drug therapy does not normally
provide a cure for psychoses but is a way of chemically controlling the symptoms of the illness.
The newer-generation antipsychotics are referred to as atypical antipsychotics, as opposed to the
older-generation drugs, which can also be thought of as conventional antipsychotics. Atypical
antipsychotics differ from conventional drugs in that they tend to have better adverse effects.
 Mechanism of action:
One thing that all antipsychotics have in common is some degree of blockage of dopamine receptors
in the brain, which decrease the dopamine concentration in the CNS. Specifically, the older
phenothiazines block the receptors to which dopamine normally binding postsynaptically in certain
areas of the CNS, such as the limbic system and the basal ganglia. These are the areas associated
with emotions, cognitive function, and motor function.
The newer atypical antipsychotic drugs block specific dopamine receptors called dopamine 2
receptors, as well as specific serotonin receptors in the brain known as serotonin 2 receptors. These
more refined mechanisms of action of atypical are responsible for their improved efficacy and safety
profiles, compared with older drugs.
 Adverse effects:
Common adverse effects include CNS effects like drowsiness, neuroleptic malignant syndrome (is
a potentially lifethreatening adverse effect may include high fever, unstable blood pressure),
extrapyramidal symptoms (they are involuntary motor symptoms similar to those associated with
parkinson’s disease). Theoretically these effects are possible with atypical antipsychotics as well as
older drugs. However, evidence suggests that the incidence is lower with the newer drugs.
Cardiovascular effects include postural hypotension, in addition, electrocardiogram changes.
 Lithium
The original drugs still currently available that can effectively alleviate the symptoms of acute mania
are the lithium salts lithium carbonate and lithium citrate.
Lithium is also effective for the maintenance treatment of bipolar disorder. One possible explanation
for its effectiveness is that it potentiates serotonergic neurotransmission.
A variety of medications may be used in conjunction with lithium to regulate mood or achieve stability
in manic or hypomanic patients include benzodiazepines, antipsychotic drugs, antiepileptic drugs,
and dopamine receptor agonists.
The antiepileptic valproic acid, lamotrigine, and carbazepine are commonly preferred to lithium
because lithium has a narrow therapeutic range and requires blood level monitoring. These drugs
are often effective in treating mania, hypomania, and to lesser degree, depressive symptoms. Other
evidence has shown that the atypical antipsychotic drugs risperidone, olanzapine,and ziprasidone
can also be effective in treating mania and hypomania.
Nursing Implications:
 Provide simple explanations about the drug, its effects, and the length of time before
therapeutic effects can be expected
 Advise patients to avoid abrupt withdrawal
 Advise patients to change positions slowly to avoid postural hypotension and possible injury
 The combination of drug therapy and psychotherapy is emphasized because patients need to
learn and acquire more effective coping skills
 Only small amounts of medications should be dispensed at a time to minimize the risk of
suicide attempts
 Simultaneous use of these drugs with alcohol or other CNS depressants can be fatal
 Antidepressants
 Inform patients that it may take several weeks to see therapeutic effects, monitor
patients closely during this time, assess for suicidal tendencies, and provide support
 Tricyclics may need to be weaned and discontinued before undergoing surgery to
avoid interactions with anesthetic drugs
 Monitor for adverse effects, and discuss with patients
 Encourage patients to wear medication ID badges naming the drugs being taken
 Caffeine and cigarette smoking may decrease effectiveness of medication therapy
 Antipsychotics
 Instruct patients to wear sunscreen because of photosensitivity
 Tell patients to avoid taking antacids or antidiarrheal preparations within 1 hour of a
dose
 Long-term haloperidol therapy may result in tremors, nausea, vomiting, or
uncontrollable shaking of small muscle groups; report these symptoms to the
physician
 Oral forms may be taken with meals to decrease GI upset
 These drugs may cause drowsiness, dizziness, or fainting; instruct patients to change
positions slowly
 Monitor for therapeutic effects
 Monitor mental alertness, cognition, affect, mood, ability to carry out activities of daily
living, appetite, and sleep patterns
 Monitor potential for self-injury during the delay between the start of therapy and
symptomatic improvement
 For antidepressants
 Improved sleep patterns and nutrition
 Increased feelings of self-esteem
 Decreased feelings of hopelessness
 Increased interest in self and appearance
 Increased interest in daily activities
 Fewer depressive manifestations or suicidal thoughts/ideations
 For antipsychotics
 Improved mood and affect
 Alleviation of psychotic symptoms and episodes
 Decreased hallucinations, paranoia, delusions, garbled speech, and inability to
cope
 For lithium
 Less mania
 Therapeutic lithium levels of 0.6 to 1.2 mEq/L