Download PHARMACOLOGY IN PSYCHIATRIC CARE

PHARMACOLOGY IN PSYCHIATRIC CARE
NURSING ALERT!!!
Drug Risks in Pregnancy
• Category A
Clinical studies have not identified risk to fetus in any trimester
• Category B
Animal studies show no effect on fetus, but no studies in humans
OR animal studies show adverse effect, but no risk demonstrated in studies of pregnant women in 1st or
other trimester
• Category C
Animal studies show risk to fetus & there are no human studies
Risk cannot be ruled out, but benefit may outweigh risks
• Category D
Positive risk to human fetus if used during pregnancy
Potential benefits may outweigh potential risks
• Category X
Studies show fetal abnormalities or adverse reactions that indicate risk
Use of drug in pregnancy is contraindicated
No potential benefit that outweighs the risks
ANTIPSYCHOTICS
• Control symptoms of psychosis
• Calm without sedation
• First-generation drugs include Haldol, Thorazine
• Second-generation (atypical) drugs include Risperdal, Abilify
INDICATIONS & EVIDENCE FOR EFFECTIVENESS
• Schizophrenia and manic-depressive psychosis
• “Positive” symptoms of schizophrenia (hallucinations, delusions, disorganized thought processes, paranoia)
• “Negative” symptoms of schizophrenia (withdrawal, lack of initiative, failure to maintain hygiene)
FIRST vs. SECOND GENERATION
• Second generation have different and fewer side effects
• Second generation cost more
GROUPING BY POTENCY CLASS
• Grouping by amount of drug required to achieve effect
• High potency—only small amount will have significant effects
• Low potency—only large amount will have significant effects
• Tagamet & Antipsychotics
NURSING ALERTS!!!
Tagamet (cimetidine) will lower the effectiveness of antipsychotics
• Epinephrine & Thorazine
Administration of epinephrine to persons taking phenothiazines such as Thorazine may result in severe
hypotension
NON-ANTIPSYCHOTIC DRUGS USED TO TREAT PSYCHOSIS
• Benzodiazepines
• Antidepressants
• Mood stabilizers
• Other agents to counteract side effects
DOSE/ADMINISTRATION
• Injections work within 15–30 minutes
• PO meds work within one to four hours
• Liquid preps work faster than pills
• Foods, coffee, smoking, drugs can decrease oral absorption
• Dosage varies with drug and physician
ACTION
• All antipsychotics bind to brain dopamine receptors
• Produce degree of indifference to both external and internal stressful stimuli
• Exert calming effect without reducing alertness and sensitivity to pain
DRUG INTERACTIONS
• Cimetidine
• Anticonvulsants
• Lithium
• Tricyclic antidepressants
• Fluoxetine
• SSRIs
• Some cardiac drugs
• Epinephrine
• Caffeine
• Antacids
SIDE EFFECTS
• Constipation
• Dry mouth
• Blurred vision
• Postural hypotension
• Urinary hesitancy or retention
• Weight gain
• Sedation
ADVERSE EFFECTS
• Akathisia
• Dystonia
• Drug-induced parkinsonism
• Tardive dyskinesia
NEUROLEPTIC MALIGNANT SYNDROME
• Sudden fever
• Rigidity
• Tachycardia
• Hypertension
• Decreased levels of consciousness
Differentiating Akathisia, Anxiety, & Agitation
• Akathisia
Describing feeling “antsy”
Inability to sit still
Pacing the floor
Not being frightened
• Anxiety
Expressing thoughts of worry or concerns
Having fears, even if unable to state the source of worry
Often having somatic symptoms
• Agitation
Exhibiting escalating anxiety and anger
Vocalizing concerns / complaints
Possible demonstrating destructive behavior
TRICYCLIC and RELATED ANTIDEPRESSANTS
• Were the first antidepressants
• Are only given orally
• Sedation causes improved sleep patterns
• Antidepressant effect seen in four to six weeks
• Also used for panic disorder, obsessive-compulsive disorder, psychotic depression
SIDE EFFECTS
• Blurred vision
• Dry mouth
• Rapid heart rate
• Constipation
• Urinary retention
• Weight gain
• Sedation
• Hypotension
• Postural hypotension
• Dizziness
NURSING ALERT!!!
• Alcohol and Antidepressants
Alcohol adds to the CNS depression produced by antidepressants, & clients must be made aware that
alcohol-related impairment occurs after fewer drinks than in persons not taking these medications
SELECTIVE SEROTONIN REUPTAKE INHIBITORS
•
•
•
•
•
•
Excellent antidepressant effect
First-line medications for depressed individuals
More expensive
Valuable for other conditions
Work in two to four weeks
May interact rarely and seriously with MAOIs
SIDE EFFECTS
SSRIs are the best tolerated antidepressants
May cause:
• Anxiety
• Headache
• Gastrointestinal disturbance
• Disturbances of sexual functioning
• Akathisia
• Serotonergic syndrome
MONOAMINE OXIDASE INHIBITORS
• Tried when tricyclics and SSRIs fail
• Treat panic disorder, anxiety disorders, and bulimia
• Work in three to four weeks
SERIOUS DRUG INTERACTIONS
• Other antidepressants
• Narcotic analgesics (especially Demerol)
• Dextromethorphan
• Decongestants and cold medications
• Sympathomimetics
• May cause hypertension, fever, coma, and even death
NURSING ALERT!!!
• MAOIs and Robitussin (dextromethorphan)
Persons taking MAOIs must be warned that OTC medications with dextromethorphan (a common ingredient
in cough medication) interact with the MAOIs producing hypertension, fever, & possibly coma
• Demerol and MAOIs
* Demerol (meperidine) should not be given to persons taking MAOIs
* There is a severe interaction between MAOIs and demerol that produces fever, hypertension, & coma
SERIOUS FOOD INTERACTIONS
• Foods containing tyramine (more than 25mg/serving)
• Sharp (old) cheddar cheese
• Salami
• Sauerkraut
• Beer and wine (with yeast)
• Yeast extracts
• Caviar
• Fava beans
• Ripe avocados
• Foods to be consumed in moderation:
Chocolate
Coffee
SIDE EFFECTS
• Decreased heart rate
• Hypotension
• Dizziness/syncope
• Anticholinergic symptoms
• Central nervous symptoms
• Sexual dysfunction
• Weight gain
MISCELLANEOUS ANTIDEPRESSANTS
• Serotonin noradrenergic reuptake inhibitors (SNaRIs)
• Selective noradrenaline reuptake inhibitor (NaRI)
• Noradrenergic and specific serotonergic antidepressants (NaSSAs)
• Xanax—(aprazolam)
• BuSpar—(buspirone)
MOOD STABILIZERS
• Management of mania
• Lithium should have regular serum drug level screening
• Mechanism of action not understood
DRUG AND FOOD INTERACTIONS
May affect lithium levels:
• Diuretics and low-salt diets
• NSAIDs
• Prescription anti-inflammatory drugs
Haldol may cause permanent CNS damage
Other drugs that may cause harm
• Aminophylline
• Erythromycin
• Cimetidine
SIDE EFFECTS
• Thirst
• Polyuria
• Tremor
• Weight gain
• Chronic diarrhea
• Thyroid enlargement
• Dizziness
• Drowsiness
• Agranulocytosis
• Liver damage
DRUGS FOR TREATING ANXIETY AND SLEEP DISORDERS
•
•
•
•
•
Most commonly benzodiazepines
Buspirone, antidepressants, beta blockers
Antihistamines, barbiturates, antipsychotics
Illegally obtained drugs
Alcohol
PHARMACOLOGY
• Benzodiazepines frequently diverted to street sales
• May produce dependence
• Work quickly
• Prolong daytime drowsiness
•
•
•
•
•
INTERACTIONS & SIDE EFFECTS
Alcohol is addictive with sedative effects
Can be fatal
Main side effect is sedation
Occasionally amnesia
May cause physical dependence
DRUGS USED TO TREAT SUBSTANCE ABUSE AND DEPENDENCY
• Methadone—oral methadone substituted for heroin injection
• Disulfiram—causes extreme discomfort when alcohol is ingested
• Nicotine replacement
• Opioid receptor antagonists
STIMULANT DRUGS
• Cyclert and Ritalin
• May be useful as antidepressants
• Useful in narcolepsy and ADD
• Long-term administration to children has caused controversy
NURSING ALERT!!!
• Thiamine and Alcohol-Induced Hypoglycemia
* Thiamine must be given when hydrating alcoholics.
* The alcoholic person is hypoglycemic.
* When hydration increases glucose metabolism, the client uses up thiamine stores & there is an increased
body requirement for thiamine.
* Failure to give thiamine prior to fluids & glucose may result in permanent neurological damage.