The short answer
Avoid self-starting yohimbine while taking phenelzine. Yohimbine can increase sympathetic activity, and phenelzine warns against interacting stimulants. This assessment is based on pharmacology and medication precautions, not a verified trial of the two together.
What this answer covers
Oral yohimbine as the selected compound with oral phenelzine. Yohimbe bark is not treated as an interchangeable dose or composition, and alpha-yohimbine/rauwolscine is not automatically included.
- Supplement or preparation
- Yohimbine
- Medication ingredient
- phenelzine
The concern is an added adrenergic effect
Yohimbine blocks alpha-2 adrenergic receptors and can increase norepinephrine activity. This differs from a serotonin-precursor interaction and is relevant to phenelzine's warning about sympathomimetic substances.
The human study has limits
A small crossover study found an increase in diastolic pressure in participants with untreated hypertension, but not the same response in healthy controls. It did not test phenelzine, so it cannot quantify the risk of this combination.
Yohimbine is not a standardized bark dose
A yohimbe herb product may contain varying amounts of yohimbine and other constituents. Do not convert a purified-compound study into a safe amount of bark extract, or transfer it to alpha-yohimbine.
Discuss use before taking it
No hours-apart schedule has been verified as protective. Ask the prescriber about the actual product rather than changing phenelzine yourself. Severe headache, chest pain, fainting or marked blood-pressure symptoms require urgent assessment.
Evidence and practical considerations
Side effects & toxicity
A placebo-controlled yohimbine study found norepinephrine increases and a diastolic-pressure rise in hypertensive participants. Applied to phenelzine's sympathomimetic warning, this supports a precaution, not proven exact-pair clinical causation.
- Exact scope
- Oral yohimbine as the selected compound with oral phenelzine. Yohimbe bark is not treated as an interchangeable dose or composition, and alpha-yohimbine/rauwolscine is not automatically included. with Oral phenelzine tablets; current sulfate-tablet labeling uses the named active ingredient.
- Medication form and route
- oral
What remains uncertain
- The study did not include phenelzine. Not all participants had the same pressure response, and the article cannot set a safe yohimbine dose with an MAOI.
Factors that may matter: Exact supplement preparation and complete concomitant-medication list require assessment..
Read the supporting source summaries
Source 1: Current U.S. prescribing information
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: Patients prescribed oral phenelzine sulfate tablets.
The label prohibits sympathomimetics, L-tryptophan, L-tyrosine, phenylalanine and serotonergic agents. It warns about excessive caffeine and high-tyramine exposures.
How this applies: Primary authority for phenelzine oral-tablet precautions; each article identifies whether the supplement is named or the application is a constituent/class inference.
Regulatory instructions do not quantify an exact-pair event rate or validate every botanical formulation.
Source 2: Randomized crossover human trial
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: 25 healthy volunteers and 29 untreated hypertensive patients.
Norepinephrine increased in both groups; a significant diastolic-pressure increase occurred in the hypertensive group only.
How this applies: No phenelzine coadministration. The results support a pharmacologic concern, not an exact-pair event rate or universal response.
No phenelzine coadministration. The results support a pharmacologic concern, not an exact-pair event rate or universal response.
Research assessment: · Open full citations ↗
Review and change history
- Publication status
- Published research summary
- Clinical review
- Not yet recorded
| Date | Update |
|---|---|
| Article prepared | |
| Initial targeted research draft. Inspected source material, adjudicated the current checker statements, and recorded preparation limits. Clinical review has not occurred. | |
| Research summary published |
Article revision: bf8937aa4816ceaa
This guide brings together the evidence records used by our interaction checker. Each finding retains its own preparation limits, research date, and source summaries.
Full citations require verification. Reading this answer and the source summaries does not.
Taking other supplements or medications?
Use the checker to explore your other combinations. Ask a pharmacist to review the exact products, amounts and medical conditions in your complete list.
Open the interaction checkerInformation, not medical advice. Do not change prescribed treatment based on this guide.