Monoamine Oxidase Inhibitor

Aka: Monoamine Oxidase Inhibitor, MAO inhibitor, Phenelzine, Nardil, Tranylcypromine, Parnate

1. Indications: Comorbid Depression
   1. Anxiety Disorder
   2. Atypical Depression
   3. Refractory Depression
   4. Bulimia
   5. Social Phobia
2. Mechanism
   1. Inhibits monoamine oxidase
   2. Increases synaptic concentration of monoamines
      1. Serotonin
      2. Norepinephrine
3. Precautions
   1. Tyramine-free diet must be followed
      1. Continue for two weeks after stopping medication
      2. See Tyramine Containing Foods
   2. Stop 2 weeks before starting another Antidepressant
   3. Taper Nardil slowly when stopping
      1. See Antidepressant Withdrawal
      2. Reduce dose by 15 mg/day every 2 weeks (or 10%/week)
4. Preparations: Hydrazine
   1. Isocarboxazid (Marplan): No longer manufactured in U.S.
      1. Dosing: 10 mg PO bid
      2. Maximum: 60 mg per day
   2. Phenelzine (Nardil)
      1. Dosing: 15 mg PO tid
      2. Maximum: 90 mg per day
5. Preparations Non-hydrazine
   1. Tranylcypromine (Parnate)
      1. Dosing: 10-40 mg/day in divided doses
      2. Maximum: 60 mg per day
   2. Parkinsonian agents
      1. Selegiline (Eldepryl)
6. Complications
   1. Hypertensive Crisis (life-threatening)
      1. Occurs if tyramine or Sympathomimetic exposure
   2. Serotonin Syndrome
      1. Occurs with concurrent use of Serotoninergic drug
7. Drug Interactions (Do not use with these medications)
   1. Tyramine Containing Foods
   2. Sympathomimetics (Ephedra, Ephedrine)
   3. Serotoninergic medications
   4. Selective Serotonin Reuptake Inhibitors (SSRI)
8. Adverse Effects
   1. Anti-Histaminergic effects
      1. Dizziness
      2. Sedation
      3. Orthostatic Hypotension
      4. Weight gain
   2. Dopaminergic effects
      1. Insomnia
      2. Myoclonal jerks
   3. Serotoninergic Effects
      1. Sexual dysfunction
      2. Headache
   4. Anticholinergic Toxicity
      1. Dry Mouth
      2. Constipation
      3. Blurred Vision
      4. Urinary hesitancy
      5. Nausea
      6. Memory Dysfunction
   5. Other Effects
      1. Peripheral edema
      2. Weakness