Dopamine and Isocarboxazid: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Isocarboxazid
Dopamine
No brand names on record
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
An increased risk of hypertensive crisis (headache, hyperpyrexia, hypertension)
Interaction Deep Dive
Concurrent use of isocarboxazid with DOPamine (sympathomimetics) is contraindicated as it may precipitate hypertension, headache, and related symptoms. During isocarboxazid therapy, it appears that some patients are particularly vulnerable to the effects of sympathomimetics when the activity of metabolizing enzymes is inhibited4. Sympathomimetics, such as DOPamine, with indirect/mixed activity can release large amounts of norEPINEPHrine that have accumulated during MAO inhibition and thus cause excessive noradrenergic stimulation resulting in increased blood pressure. More direct acting agents like norEPINEPHrine, EPINEPHrine, and isoproterenol have minimal interaction liability 23.
Why it happens (mechanism)
Increased norEPINEPHrine availability
Literature reports
4 reports — tap to read
a) DOPamine is metabolized by MAO, thus DOPamine effects will be prolonged in patients receiving MAO inhibitors. The interaction could result in severe hypertension and/or cardiac arrhythmias. No more than one-tenth of the usual dose of DOPamine should be given to patients receiving MAO inhibitors 1.
b) Severe headaches and hypertensive crises are well-documented in the literature as being associated with this combination. Other potential reactions include nausea, vomiting, cardiac arrhythmias, chest pain, intracranial bleeding, circulatory failure, hyperpyrexia, and death 56.
c) Sympathomimetic drugs to be avoided while on isocarboxazid include amphetamines, ePHEDrine, metaraminol, phenylephrine, phenylpropanolamine, and mephentermine 78.
d) The mechanism involved with this interaction is felt to be the release of catecholamine by the sympathomimetic drug. This results in liberation of a larger amount of norEPINEPHrine which is then available to combine with the receptor 6. Sympathomimetics, such as DOPamine, with indirect/mixed activity can release large amounts of norEPINEPHrine that have accumulated during MAO inhibition and thus cause excessive noradrenergic stimulation resulting in increased blood pressure. More direct acting agents like norEPINEPHrine, EPINEPHrine, and isoproterenol have minimal interaction liability 23.
Common questions
Can I take Dopamine and Isocarboxazid together?
An increased risk of hypertensive crisis (headache, hyperpyrexia, hypertension) Always confirm with your pharmacist or prescriber before making any change.
How serious is the Dopamine and Isocarboxazid interaction?
It is rated contraindicated. These should generally not be used together.
How quickly could this interaction happen?
The documented onset is "rapid". Effects can appear quickly, often within about 24 hours of combining the drugs.
How strong is the evidence for this interaction?
The evidence is graded "probable". Good supporting evidence, though not definitively proven.
Questions for your pharmacist
- Does my dose of Dopamine or Isocarboxazid need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (8)
- Horwitz D, Goldberg LI, & Sjoerdsma A: Increased blood pressure responses to dopamine and norepinephrine produced by monoamine oxidase inhibitors in man. J Lab Clin Med 1960; 56:747.
- Smookler S & Bermudez AJ: Hypertensive crisis resulting from an MAO inhibitor and an over-the-counter appetite suppressant. Ann Emerg Med 1982; 11:482-484. PubMed
- Boakes AJ, Laurence DR, Teoh PC, et al: Interactions between sympathomimetic amines and antidepressant agents in man. Br Med J 1973; 1:311-315. PubMed
- Product Information: MARPLAN oral tablets, isocarboxazid oral tablets. Validus Pharmaceuticals LLC (per Dailymed), Parsippany, NJ, 2023. DailyMed
- Brownlee G & Williams GW: Potentiation of amphetamine and pethidine by monoamine oxidase inhibitors. Lancet 1963; 1:669.
- Goldberg LI: Monoamine oxidase inhibitors. Adverse reactions and possible mechanisms. JAMA 1964; 190:456-462. DOI
- Sjoqvist F: Psychotropic drugs (2). Interaction between monoamine oxidase (MAO) inhibitors and other substances. Proc R Soc Med 1965; 58:967-978. PubMed
- Elis J, Laurence DR, Mattie H, et al: Modification by monoamine oxidase inhibitors of the effect of some sympathomimetics on blood pressure. Br Med J 1967; 2:75-78. DOI
Keep reading about Isocarboxazid
Keep reading about Dopamine
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