Antidepressants Flashcards
According to the biogenic amine theory, depression is due to a deficiency of which two neurotransmitters in the brain?
- Serotonin (5-HT)
2. Norepinephrine (NE)
MAOa inactivates which neurotransmitters?
5-HT; NE
MAOb inactivates which neurotransmitter?
Dopamine (DA)
What is the mechanism of action of MAOIs?
inactivation of MAO, thereby increasing levels of 5-HT, NE, and DA in presynaptic neurons with subsequent leakage of neurotransmitter into the synaptic cleft
Name 3 nonselective MAOIs:
- Transylcypromine
2l Phenelzine - Isocarboxazid
Selegiline is commonly used in the treatment of which disease?
Parkinson disease
MAOa also inactivates which monoamine commonly found in certain cheeses (aged), alcoholic beverages, fish, chocolates, red wines, and processed meats?
Tyramine (inactivated by MAO in the GI tract)
MAOIs are the drugs of choice for treating what type of depression?
Atypical depression
How long does it take to see antidepressant effects in patients who are started on an MAOI?
2-4 weeks
How long should a patient wait from the time o discontinuing an MAOI to the time of starting a new antidepressant med?
At least 2 weeks
What are the adverse effects of MAOIs?
Orthostatic hypotension; xerostomia; blurred vision; drowsiness; constipation; urinary retention
What life-threatening condition may develop when MAOIs and selective serotonin reuptake inhibitors (SSRIs) are used concomitantly?
Serotonin syndrome
What characterizes serotonin syndrome?
Rigidity; diaphoresis; hyperthermia; seizures; autonomic instability; myoclonus
What life threatening condition may develop when patients taking MAOIs ingest foods containing tyramine?
Hypertensive crisis
What characterizes hypertensive crisis?
Hypertension; headache; tachycardia; nausea; vomiting; stroke; cardiac arrhythmias
A serotonin-like syndrome may develop when MAOIs are used concomitantly with what common OTC med used to suppress cough?
Dextromethorphan
A serotonin like syndrome may develop when MAOIs are used concomitantly with which opiod analgesic?
Meperidine
What is the mechanism of action of tricyclic antidepressants (TCAs)?
Inhibit reuptake of 5-HT and NE into presynaptic neurons, thereby increasing neurotransmitter concentrations in the synaptic cleft
What other types of neurotransmitter and hormonal receptors, other than 5-HT and NE, are inhibited by TCAs?
Muscarininc; alpha-adrenergic; histaminergic
How long does it take to see antidepressant effects in patients who are started on a TCA?
4-6 weeks