brands

Class

• Neuroscience-based Nomenclature: serotonin, norepinephrine, dopamine reversible enzyme inhibitor (SN-RevEI)
• Reversible inhibitor of monoamine oxidase A (MAO-A) (RIMA)

Morex commonly prescribed for

(Bold for FDA approved)

How Morex works

• Reversibly blocks MAO-A from breaking down norepinephrine, dopamine, and serotonin

• This boosts noradrenergic and serotonergic neurotransmission

• MAO-A inhibition predominates unless significant concentrations of monoamines build up (e.g., due to dietary tyramine), in which case MAO-A inhibition is theoretically reversed

How long until Morex works

• Onset of therapeutic actions usually not immediate, but often delayed 2–4 weeks following adequate dosing

• If it is not working within 6–8 weeks, it may require a dosage increase or it may not work at all

• May continue to work for many years to prevent relapse of symptoms

Notable Side Effects

• Insomnia, dizziness, agitation, anxiety, restlessness

• Galactorrhea

• Rare hypertension

Life Threatening Side Effects

• Hypertensive crisis (especially when MAOIs are used with certain tyramine containing foods – much reduced risk compared to irreversible MAOIs)

• Induction of mania in patients with bipolar disorder

• Rare seizures

weight gain

unusual

sedation

not usual

What to do about Morex side effects

• Wait

• Wait

• Wait

• Lower the dose

• Switch to an SSRI or newer antidepressant

usual dosage range

• 300–600 mg/day

Dosage Forms

• Tablet 100 mg scored, 150 mg scored

long term use

• MAOIs may lose efficacy long-term

habit forming

• Dependence to MAOIs reported but rare

Renal Impairment

Use with caution

Hepatic Impairment

• Plasma concentrations are increased

• May require one-half to one-third of usual adult dose

Cardiac Impairment

• Cardiac impairment may require lower than usual adult dose

• Patients with angina pectoris or coronary artery disease should limit their exertion

Elderly

• Elderly patients may have greater sensitivity to adverse effects, but many tolerate MAOIs

• Reduction in the risk of suicidality with antidepressants compared to placebo in adults age 65 and older

Children and Adolescents

• Not recommended for use in children under age 18

• Carefully weigh the risks and benefits of pharmacological treatment against the risks and benefits of nontreatment with antidepressants and make sure to document this in the patient’s chart

• Monitor patients face-to-face regularly, particularly during the first several weeks of treatment

• Use with caution, observing for activation of known or unknown bipolar disorder and/ or suicidal ideation, and inform parents or guardians of this risk so they can help observe child or adolescent patients

Pregnancy

• Not generally recommended for use during pregnancy, especially during first trimester

• Should evaluate patient for treatment with an antidepressant with a better risk/benefit ratio

Breast Feeding

• Some drug is found in mother’s breast milk

• Effects on infant are unknown

• Immediate postpartum period is a high-risk time for depression, especially in women who have had prior depressive episodes, so drug may need to be reinstituted late in the third trimester or shortly after childbirth to prevent a recurrence during the postpartum period

• Should evaluate patient for treatment with an antidepressant with a better risk/benefit ratio