Home Drug Guide Isocarboxazid

Drug Guide

Generic Name

Isocarboxazid

Brand Names Marplan

Classification

Therapeutic: Antidepressant, Monoamine oxidase inhibitor (MAOI)

Pharmacological: Irreversible monoamine oxidase inhibitor

FDA Approved Indications

  • Major depressive disorder (approved for treatment-resistant depression)

Mechanism of Action

Isocarboxazid inhibits monoamine oxidase enzymes (MAO-A and MAO-B), leading to increased levels of neurotransmitters such as norepinephrine, serotonin, and dopamine in the brain, which helps improve depressive symptoms.

Dosage and Administration

Adult: Typically, 10-20 mg twice daily, titrated gradually based on response and tolerability.

Pediatric: Not approved for pediatric use.

Geriatric: Use with caution; start at lower doses due to increased risk of side effects.

Renal Impairment: Adjust dosing based on clinical response; no specific guidelines.

Hepatic Impairment: Use cautiously; monitor closely.

Pharmacokinetics

Absorption: Well absorbed orally.

Distribution: Widely distributed; crosses the blood-brain barrier.

Metabolism: Metabolized in the liver, primarily via oxidation.

Excretion: Excreted mainly in urine.

Half Life: Approximately 3-4 hours; irreversible inhibition of MAO lasts longer.

Contraindications

  • Concurrent use with other serotonergic drugs, tyramine-rich foods, or certain medications such as other MAOIs, SSRIs, SNRIs, tricyclic antidepressants, and sympathomimetics.

Precautions

  • History of hypertensive crisis, liver disease, or cerebrovascular disease. Risk of hypertensive crisis if dietary restrictions are not followed.

Adverse Reactions - Common

  • Dizziness (Common)
  • Dry mouth (Common)
  • Insomnia (Common)

Adverse Reactions - Serious

  • Hypertensive crisis (Serious (rare, but potentially fatal))
  • Serotonin syndrome (Serious (if combined with other serotonergic drugs))
  • Liver toxicity (Rare)

Drug-Drug Interactions

  • Other antidepressants, sympathomimetics, meperidine, alcohol, certain pain medications.

Drug-Food Interactions

  • Tyramine-rich foods (aged cheeses, cured meats, fermented foods) can precipitate hypertensive crisis.

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor blood pressure regularly, assess for signs of hypertensive crisis, check liver function tests.

Diagnoses:

  • Risk for hypertensive crisis
  • Risk for serotonin syndrome

Implementation: Educate patient about dietary restrictions, monitor for adverse effects, advise about drug interactions.

Evaluation: Effectiveness of depression treatment, absence of hypertensive crises or adverse reactions.

Patient/Family Teaching

  • Adhere strictly to dietary restrictions, report symptoms of hypertensive crisis (severe headache, palpitations, stiff neck), do not combine with other serotonergic drugs without medical advice.
  • Do not stop medication abruptly.
  • Carry medical identification indicating MAOI use.

Special Considerations

Black Box Warnings:

  • Risk of hypertensive crisis with dietary tyramine and certain medications.
  • Serious drug interactions can lead to serotonin syndrome.

Genetic Factors: None specifically noted.

Lab Test Interference: None known.

Overdose Management

Signs/Symptoms: Severe hypertension, hyperthermia, convulsions, coma.

Treatment: Supportive care, control blood pressure with agents like nitroprusside, gastric lavage if recent ingestion, activated charcoal.

Storage and Handling

Storage: Store at room temperature, away from moisture and heat.

Stability: Stable within specified date, check manufacturer instructions.

🛡️ 5 Critical Medication Safety Tips for Nurses

1

Triple-Check High-Risk Medications

Always have another nurse verify insulin, heparin, warfarin, and chemotherapy drugs. These "high-alert" medications cause the most serious errors. Check concentration, dose calculation, and pump settings twice.

2

Know Look-Alike, Sound-Alike Drugs

Common mix-ups: hydromorphone/morphine, Celebrex/Celexa, Zyprexa/Zyrtec. Always use BOTH generic and brand names, read labels twice, and use barcode scanning when available. One wrong letter can be fatal.

3

Assess Before AND After Giving Meds

Check vitals before cardiac meds, pain levels before analgesics, and blood glucose before insulin. Always reassess within 30 minutes to evaluate effectiveness and watch for adverse reactions.

4

Watch for Drug Interactions

Common dangerous combinations: warfarin + aspirin (bleeding), ACE inhibitors + potassium (hyperkalemia), digoxin + diuretics (toxicity). Always check drug interactions before administering new medications.

5

Educate Your Patients

Teach patients medication names, purposes, major side effects, and what to report. Informed patients catch errors and improve compliance. Always encourage questions - an educated patient is a safer patient.

⚡ Remember: When in doubt, don't give it out! It's always safer to double-check than regret later.

⚠️ Medical Disclaimer

This drug guide is for educational purposes only and is NOT intended for clinical use. Always consult current prescribing information, healthcare providers, and institutional protocols before administering any medication. Do not use this information for patient care decisions.