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N402
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Nervous
system
Central
Brain
Peripheral
Spinal cord
Somatic
Motor
neurons
Sensory
neurons
Autonomic
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Autonomic Nervous
System
Sympathetic
(fight or flight)
Parasympathetic
(rest and digest)
Adrenergic
receptors
Cholinergic
receptors
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Stimulate
SNS =
adrenergic
agonists
Inhibit SNS
=
adrenergic
antagonists
Stimulate
PSNS =
cholinergics
Inhibit
PSNS =
anticholinergics
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Adrenergics = sympathomimetics
Andrenergic antagonists = sympatholytics
Cholinergics = parasympathomimetics
Anticholinergics =parasympatholytics (aka
cholinergic blocking agents)
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Identification of the correct medication requires
Identifying the maladaptive or undesired response
 Determine the source
 Do we want to interrupt the source? Or,
 Do we want to stimulate a counteracting source?
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Intense anxiety
Other anxiety
disorders
Generalized
anxiety disorder
Phobias
Panic disorder
Social anxiety
disorder
Obsessive
compulsive disorder
PTSD
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Limbic system
Emotion
Behavior
Motivation
Long term memory
Reticular system
Sleep-wake transition
Attention
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Tricyclic antidepressants (TCAs)
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Monamine oxidase inhibitors (MAOIs)
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Avoid use with heart disease, asthma
Example: Amitriptyline (Elavil)
Avoid use with diabetes (potentiates insulin)
Selective serotonin reuptake inhibitors (SSRIs)
Safer than other classes
 Can cause sexual dysfunction
 Examples: Escritalopram (Lexapro), Citalopram
(Celexa)
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Preferred drugs for many anxiety disorders
and for insomnia
Less physical dependence
Do not produce respiratory depression
Short term treatment of insomnia
Examples: Diazepam (Valium),
Lorazepam (Ativan)
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The treatment is directed to the cause of seizure:
Infection
Neoplasm
Trauma
Pediatric
disorder
Metabolic
disorder
Vascular
disease
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Disturbance of brain electrical activity
Affects consciousness, motor activity,
sensation
May be either generalized or partial
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Produced by entire brain
Symptoms
Generalized tonic-clonic
(Grand-mal)
Unconsciousness, convulsions, general
rigidity
Absence
Brief loss of consciousness
Myoclonic
Sporadic jerking movements
Clonic
Repetitive jerking movements
Tonic
Muscle stiffness and rigidity
Atonic
Loss of muscle tone
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Produced by small part of brain
Symptoms
Simple:
Motor
Sensory
Psychological
Jerking, muscle rigidity, spasms
Unusual sensations of 5 senses
Memory or emotional disturbances
Complex
Automatisms such as lip-smacking,
fidgeting, chewing, walking
Partial with secondary generalization
Initially appropriate, self-preserving
actions that evolve into loss of
consciousness and convulsions
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Stimulate influx
of chloride ions
(associated with
GABA)
Delay influx
of calcium
Delay influx
of sodium
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Gamma-amniobutyric acid
Primary inhibitory transmitter in the brain
Signals other cells to subdue them
Examples: Phenobarbital (Luminal), Diazepam
(Valium)
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Phenytoin (Dilantin) is oldest and most
commonly prescribed antiseizure drug
Narrow safety range
 Frequent monitoring of drug level required
 Can trigger seizures if used with TCAs
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Valproic acid (Depakene, Depakote)
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Preferred for absence seizures
Useful in bipolar disorder
Used alone or in combination
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Seizures may be precipitated or enhanced by…
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Reduction or inadequate treatment with antiepileptic
drugs (AEDs)
Withdrawal of alcohol or other sedative agents
Administration of central nervous system stimulants
and anticholinergics including over the counter
antihistamines
Most dopamine blocking agents
Newer antipsychotics, particularly clozapine (Clozaril)
Antidepressants, especially buproprion (Wellbutrin)
Immune suppressants such as cyclosporine
Antibiotics such as quinolones or imipenem/cilastatin
Toxins (various)
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Vital signs, mental status
Drug levels, hepatic function
Level of consciousness
Emotional status—increased risk of depression
Assess gums and oral hygiene—gingival
hyperplasia)
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“Depressed affect”
At least 5 of 10 common symptoms of
depression
Symptoms last a minimum of 2 weeks
Depression may be…
Clinical depression
 Situational depression
 Postpartum depression
 Seasonal affective disorder
 Psychotic depression
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Some cultures affix a greater stigma to
depression than others
Depression may not be discussed or
acknowledged
May be acknowledged in terms of physical
(somatic) manifestations only
Consider undiagnosed
depression particularly in
Asian, Hispanic cultures.
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Physical
assessment
ECT if
unresponsive
Complete
history
Pharmacotherapy
Counseling
Behavioral
therapies
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TCAs
SSRIs
Atypicals
MAOIs
Inhibit reuptake
of norepi and
serotonin
Primarily used for
major depression
Orthostatic hypotension can occur
Rarely, cardiac
dysrhythmias
E.g.,
Amitriptyline
(Elavil)
Slow the reuptake
of serotonin
Major advantage
is fewer side
effects
Beneficial effects
occur more
quickly
Sexual
dysfunction in ≤
70% both men
and women
E.g., Citalopram
(Celexa), Escitalopram (Lexapro).
Sertraline (Zoloft)
Some slow
reuptake of
serotonin and
norepi
Also affect level of
dopamine
Shorter half-life
than TCAs
E.g., Buproprion
(Wellbutrin)
Buproprion
lowers seizure
threshold
Limit breakdown
of norepi, dopamine, serotonin in
the CNS
High degrees of
drug-drug and
food-drug interactions (foods
containing tyrine,
cheeses, sausage,
tap beer, sauerkraut, red wine,
soy sauce) →
hypertensive
crisis
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May occur when SSRI taken with another
medicine affecting the reuptake of serotonin
E.g., MAOI, TCA, Lithium
Serotonin accumulates in the body
Mental status changes
HTN
Tremors, ataxia
Hyperpyrexia, sweating
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May be due to dysfunction of dopamine,
norepinephrine, or serotonin
Easy distractibility
Difficulty focusing on 1 task at a time
Difficulty remembering
Inability to stay still
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Mainstay is CNS stimulants to increase
alertness and focus
May create increased hyperactivity
Adverse effects: insomnia, nervousness,
anorexia, weight loss
E.g., amphetamine-racemic mixture (Adderall)
amd methylphenidate (Ritalin)
Nonstimulants are available
May be less effective, used adjunctively
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Acute pain is limited; chronic pain ≥6 months
Nocioceptive
(Tissue damage)
Psychogenic
(caused,
increased by
psychological
factors)
Neuropathic
(Nerve
damage)
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Opioids
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Non-opioids
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May be naturally occurring or synthetic
Classified as highly effective or moderately effective
Constipation with both classes
Respiratory depression with highly effective types
NSAIDs
Combination products
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Hepatotoxicity from nonnarcotic component
E.g., Vicodin (hydrocodone and acetaminophen) and
Tylenol with codeine
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Tylenol #2
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Tylenol #3
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Acetaminophen 300 mg
Codeine phosphate 15 mg
Acetaminophen 300 mg
Codeine phosphate 30 mg
Tylenol #4
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Acetaminophen 300 mg
Codeine phosphate 60 mg
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Opioid intoxication is a medical emergency
because of severe respiratory depression
Opioid antagonists block opioid activity
Can reverse symptoms of addiction, toxicity,
and overdose
Naloxone (Narcan) given IV 0.4 to 2 mg every
2-3 minutes up to 10 mg
Also available intranasal
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Tolerance develops quickly
More drug is required to achieve the euphoria
Withdrawal symptoms can persist for a week or
more
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Agitation, anxiety, insomnia
Muscle aches, abdominal cramping
Nausea, vomiting, diarrhea
Oral methadone limits withdrawal symptoms
without euphoria
Allows patient to return to functional activity
Continued use required until patient elects to enter
withdrawal treatment program
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Cyclooxygenase enzymes
Released in response to inflamed tissue
Inhibition of COX can provide relief from
symptoms of inflammation and pain
COX-1 is found to protect gastric mucosa
Therefore, inhibition of COX-1 is not always
desirable
Inhibition of COX-2 is desirable to provide pain
relief
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Aspirin, ibuprofen available OTC
Aspirin has greater anti-platelet activity
Both can cause GI bleeding; aspirin has a
greater risk
Ibuprofen may be given parenterally
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Tramadol (Ultram)
weak opioid activity
Inhibits reuptake of serotonin
and norepinephrine
Tramadol!
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Alzheimer’s
(loss of brain
function)
Parkinson’s
(loss of
dopamine)
Multiple
sclerosis
(demyelination
of neurons)
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Drugs are intended to restore dopamine and
acetylcholine balance in the brain
Levodopa is a precursor of dopamine synthesis
Creates increased synthesis of dopamine
Levodopa can cross the blood-brain barrier and
enter CNS
Often used in combination with carbidopa to
enhance effects
Example: levodopa-carbidopa-entacapone
(Stalevo)
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Inhibit the effect of acetylcholine’s stimulation
of neurons to decrease symptoms
Not as effective as dopaminergic drugs for
severe Parkinson’s
Used early in disease
Sedation, tachycardia, hypotension
Example: benztropine
(Cogentin)
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Goal is to increase effects of acetylcholine to
enhance function of brain synapses
Acetylcholine is broken down by acetylcholinesterase
Therefore, drugs are designed to inhibit
acetylchoninesterase
Example: Donepezil (Aricept)
Useful in mild-to-moderate disease
 Results evident after 6 months
 Does not reverse disease
 GI, CNS, and musculoskeletal side effects
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