Isocarboxazid

Generic Name: Isocarboxazid

Brand Names: Marplan

Drug Class: MAOIs

Similar Class Drugs: Selegiline, Phenelzine

Available Dosage Form: Oral tablet

What is Isocarboxazid?

Isocarboxazid is used to treat depression and anxiety-related behaviors. Isocarboxazid was sought for its anti-depressive effects when first-line agents have failed to improve major depressive disorder in adults.²

Lack of mood-regulating monoamines in the synaptic cleft is a precursor for the pathophysiology of depression. Monoamine oxidase is an enzyme that catalyzes the uptake of monoamine neurotransmitters into the presynaptic neuron. Isocarboxazid, an irreversible monoamine oxidase inhibitor, downregulates enzymes monoamine oxidase A, B and prolongs the mood regulator effects of monoamines.

Randomized controlled trials that evaluated the long-term efficacy and safety of the drug remain inconclusive.² A shortage of Isocarboxazid-related studies has declined its utilization as a first-line agent for depression. For this reason, clinicians are inclined towards safer alternatives for long-term use. However, treatment regimens for refractory depression should not exclude Isocarboxazid if other agents fail to improve the condition.

Elevations in serum aminotransferase indicate compromised liver function and have been reported with the use of MAOIs¹. Nonetheless, the impairment is self-limiting and does not require the discontinuation of treatment. Few MAOIs have been linked to causing acute liver injury; however, instances of liver injury with Isocarboxazid are yet to come to the surface.

How to use Isocarboxazid?

Isocarboxazid is only available on prescription. Physicians adjust dosages according to individual requirements. The initial dosage is one tablet of 10 mg taken twice per day. Increased dosages are added at subsequent visits according to the severity of your condition and tolerance. The maximum recommended dosage is 60 mg/day. Thoroughly read the leaflet provided with the packaging.

Isocarboxazid interacts with many food and beverages. Ensure to inform your doctor about any medications you are taking. Ask your doctor about the condiments you should avoid when taking the medication. It has known interactions with other drugs. Improvement in symptoms is usually seen in 3-6 weeks.

What are the side effects of Isocarboxazid?

Common side effects with Isocarboxazid include:

-Drowsiness

-Dizziness

-Headache

-Sexual impairment

-Dry mouth

-Insomnia

-Nausea

-Diarrhea

-Constipation

-Tremors

Potential adverse effects of Isocarboxazid:

-Suicidal ideation

-Anaphylaxis (severe allergic reaction)

-Hypertensive crisis

-Manic episodes

-Withdrawal symptoms

-Serotonin syndrome

-Hepatoxicity

Who should not use Isocarboxazid?

-Those with hypersensitivity to the drug

-Those with tumors of the adrenal gland

-Those with cerebrovascular disorders

-Those with renal impairment

-Those with liver injury

-Those with hypotension

References

1. LiverTox: Clinical and Research Information on Drug-Induced Liver Injury [Internet]. Bethesda (MD): National Institute of Diabetes and Digestive and Kidney Diseases; 2012-. Isocarboxazid. [Updated 2020 Apr 8].Available from: https://www.ncbi.nlm.nih.gov/books/NBK548518/
2. Larsen JK, Krogh-Nielsen L,   The Monoamine Oxidase Inhibitor Isocarboxazid is a Relevant Treatment Option in Treatment-Resistant Depression-Experience-Based Strategies in Danish Psychiatry. Health Care Curr Rev. 2016;4(2). doi:10.4172/2375-4273.1000168