Formulary
Phenelzine: Indications, Dosing, Side Effects and Interactions
For all monoamine-oxidase inhibitors MAOIs inhibit monoamine oxidase, thereby causing an accumulation of amine neurotransmitters.
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Phenelzine: Indications, Dosing, Side Effects and Interactions
For all monoamine-oxidase inhibitors MAOIs inhibit monoamine oxidase, thereby causing an accumulation of amine neurotransmitters.
Drug action
For all monoamine-oxidase inhibitors MAOIs inhibit monoamine oxidase, thereby causing an accumulation of amine neurotransmitters.
Indications and dose
**Depressive illness**
- **Adult** (By Mouth): Initially 15 mg 3 times a day, response is usually seen within first week; dose may be increased if necessary after 2 weeks if response is not evident, increased if necessary to 15 mg 4 times a day, doses up to 30 mg three times a day may be used in hospital patients; response may not become apparent for up to 4 weeks; once satisfactory response has been achieved, reduce dose gradually to lowest suitable maintenance dose (15 mg on alternate days may be adequate).
Cautions
For all monoamine-oxidase inhibitors Acute porphyrias ; avoid in agitated patients; blood disorders; cardiovascular disease; concurrent electroconvulsive therapy; diabetes mellitus; elderly (great caution); epilepsy; severe hypertensive reactions to certain drugs and foods; surgery
Contraindications
For all monoamine-oxidase inhibitors Cerebrovascular disease; not indicated in manic phase; phaeochromocytoma; severe cardiovascular disease
Side effects
For all monoamine-oxidase inhibitors Frequency not known Akathisia; anxiety; appetite increased; arrhythmia; asthenia; behaviour abnormal; blood disorder; confusion; constipation; dizziness; drowsiness; dry mouth; dysuria; hallucination; headache; hyperhidrosis; insomnia; jaundice; nausea; paraesthesia; peripheral neuritis; postural hypotension (more common in elderly); reflexes increased; skin reactions; suicidal behaviours; tremor; vision blurred; vomiting; weight increased Side-effects, further information Risk of postural hypotension and hypertensive responses. Discontinue if palpitations or frequent headaches occur. Side-effects For phenelzine Rare or very rare Neuroleptic malignant syndrome (discontinue-potentially fatal) Frequency not known Cardiovascular insufficiency; delirium; electrolyte imbalance; fatal progressive hepatocellular necrosis; feeling jittery; fever; gastrointestinal disorder; glaucoma; hypermetabolism; hypertensive crisis; impaired driving ability; intracranial haemorrhage; lupus-like syndrome; malaise; mood altered; movement disorders; muscle tone increased; muscle twitching; nystagmus; oedema; respiratory disorders; schizophrenia; seizure; sexual dysfunction; shock-like coma; speech repetitive
Interactions
**Other interactions (5):**
- For specific precautions, refer to deferoxamine product information.
- Antidepressants: The occurrence of elevated blood pressure in patients receiving buspirone and monoamine oxidase inhibitors (phenelzine and tranylcypromine) has been reported.
- Drugs that decrease vitamin levels include: Drugs interfering with vitamin D metabolism, including antiepileptics (e.g.
- These include: Antibacterials Enhanced effects of suxamethonium with Aminoglycosides Clindamycin, polymyxins and vancomycin Piperacillin Antimalarials Quinine and chloroquine - effects of...
- Generally, an interval of 14 days is recommended for switching from an irreversible MAO inhibitor to moclobemide (e.g.
Pregnancy
For all monoamine-oxidase inhibitors Increased risk of neonatal malformations-manufacturer advises avoid unless there are compelling reasons.
Breast feeding
Avoid-no information available.
Hepatic impairment
For all monoamine-oxidase inhibitors In general, manufacturers advise avoid.
Medicinal forms
Clinical governance
**Author:** MedNext Clinical Team. **Clinical reviewer:** Dr Shameer Deen, MBBS, MS, MRCS. **Sources:** BNF, Indian Pharmacopoeia, CIMS India. **Correction:** Report errors at support@mednext.academy.
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