Pharmacology Specifics – Monoamine Oxidase Inhibitors (MAOIs) Flashcards
What are the 2 FDA approved indications for monoamine oxidase inhibitors?
Depression
Especially atypical and refractory depressions
Parkinson disease
Selegiline – oral form
What drug class do monoamine oxidase inhibitors belong to?
Antidepressant
What are the 4 non-FDA approved uses for monoamine oxidase inhibitors?
Anxiety disorders (phenelzine); i.e., Social anxiety disorder, panic disorder
Alzheimer’s disease (selegiline)
Bulimia nervosa (phenelzine)
PTSD (phenelzine)
What enzymes do monoamine oxidase inhibitors inhibit?
This results in increased levels of which three neurotransmitters?
Monoamine oxidase A and B
This results in increased levels of dopamine, serotonin and norepinephrine
What type of MAO inhibitors are phenelzine, selegiline, and tranylcypromine?
They are irreversible MAO inhibitors
How long does it take the body to replenish MAO?
2 weeks
What should be kept in mind when switching from an MAOI to another antidepressant?
It takes approximately two weeks for the body to replenish MAO, therefore there should be a two-week washout period I n order to decrease the risk of toxicity (serotonin syndrome and hypertensive crisis) from drug-drug interactions
What should a clinician do when a patient needs to switch from another antidepressant agent to an MAOI?
There should be an appropriate washout period (app. 5 half-lives) when switching from another antidepressant to a monoamine oxidase inhibitor; for most antidepressant agents this is approximately 2 weeks
Fluoxetine and Vortioxetine require a washout period of 5 and 3 weeks, respectively
What specific enzyme does selegiline inhibit at low oral doses? What is it used for the treatment of at low doses?
MAO-B
Parkinson disease
At higher doses, how does selegiline impact MAO?
What is it used for the treatment of at higher doses?
At higher doses, it is a nonselective MAO inhibitor
It is used for the treatment of depression at higher doses
Via transdermal administration, what is the advantage of selegiline? What does it inhibit?
Transdermal administration allows selegiline to avoid first pass metabolism
Selegiline inhibits MAO-A and MAO-B in the CNS selectively and does not affect the MAO activity in the G.I. tract
As a result, adherence to a strict tyramine-restricted diet is not necessarily, specifically with the 6 mg patch
Should patients be instructed to follow a tyramine-restricted diet with the 9 mg and 12 mg patch doses?
Yes; due to the lack of supporting evidence of not following such a diet
Nardil
Phenelzine
Parnate
Tranylcypromine
Emsam
Selegiline
Who manufactures Nardil?
Pfizer & multiple generic manufacturers
What route and form is Nardil administered in?
PO; tablet
What is the recommended daily dose range of Nardil?
15-90 mg daily
Who manufactures Parnate?
COVIS and multiple generic manufacturers
Similar to Nardil, what route and form is Parnate administered in?
PO; tablet
Who manufactures Emsam?
Mylan
What is the route and form of administration for Emsam?
Transdermal; patch
What is the recommended daily dosage of Parnate?
10-60 mg per day
What is the recommended daily dosage of Emsam?
6-12 mg per day
Which monoamine oxidase inhibitor is available as a 15 mg tablet only?
Nardil
Which monoamine oxidase inhibitor is only available as a 10 mg tablet?
Parnate
Emsam, the transdermal patch, is available in which three doses?
6 mg, 9 mg, and 12 mg
Which of the monoamine oxidase inhibitor is the cheapest?
Nardil
What is the recommended starting dose for Nardil in an adult patient? How much should it be safely increased per day? What’s the maximum recommended daily dose?
7.5-15 mg twice per day
It can be increased by 15 mg per day weekly
Maximum daily dose is 90 mg
What’s the maximum recommended daily dose of Nardil?
90 mg
What is the starting dose for the Emsam transdermal patch? How much is the dose safely increased? At what interval?
The starting dose is 6 mg per day (24 hours)
Increase by 3 mg per day at 2-week intervals
What is the maximum recommended daily dose of Emsam?
12 mg per day
What is the recommended starting dose for Parnate? How much should it be increased per day and at what interval?
The starting dose is 10 mg, 2x per day
It should be increased by 10 mg per day at 2-3 week intervals
What is the recommended maximum daily dose of Parnate?
60 mg per day
Generally speaking, how should monoamine oxidase inhibitors be managed in geriatric patients?
Start at the lowest dose, and titrate slowly, while assessing for side effects, such as orthostatic hypotension and potential drug-drug interactions
How should phenelzine be used in geriatric patients with regard to starting dose, increasing dose, and maximum dose?
Starting dose = 7.5 mg total daily
Increase by 7.5 mg per day weekly
Maximum dose = 60 mg per day
What’s the maximum dose of the selegiline transdermal patch used in geriatric patients?
Maximum dose of 6 mg per day (24 hours)
How should tranylcypromine be managed in geriatric patients, in other words, is a dose adjustment necessary?
No dose adjustment is needed, but start at the lowest dose, and increase gradually
Generally speaking, monoamine oxidase inhibitors should be avoided in which two specific types of patients?
They should be avoided in patients with hepatic and/or renal impairment due to the risk of reduced clearance, elevated levels and increased incidence of side effects
Which two specific monoamine oxidase inhibitors are contraindicated in patients with severe renal impairment?
Phenelzine (Nardil) and tranylcypromine (Parnate)