NSTK · 01.2026Independent supplement reference
NutriStack
Edition 1.0Updated August 1, 2026

Supplement × Prescription·Evidence index

L-Tryptophan and Phenelzine: what the published research says

PubMed indexes 7 records that name L-Tryptophan and Phenelzine together, either in the title or in an interaction, co-administration, or pharmacokinetic context. Each one is listed below with its study design and, where the abstract states one, the authors’ own conclusion, quoted and linked. This page reports that literature. It does not tell you whether to combine them.

Read this first

An evidence index, not guidance.

Every statement below is attributed to a named, dated, linked source.

This page lists published research relevant to L-Tryptophan and Phenelzine. It deliberately does not state whether the combination is safe, whether it interacts, in which direction, at what dose, or how far apart to take them.

The research

7 studies naming L-Tryptophan and Phenelzine.

Strongest relevance first: papers naming both substances in the title, then human trials and systematic reviews.

Myoclonus, hyperreflexia and diaphoresis in patients on phenelzine-tryptophan combination treatment.

Canadian journal of psychiatry. Revue canadienne de psychiatrie · 1985 · PMID 4063940

Case ReportsHuman subjects

“Three cases are presented on patients on an MAOI who developed a transient syndrome of myoclonus, hyperreflexia, jaw quivering, teeth chattering and diaphoresis after L-Tryptophan was added. Caution is advised when considering the addition of a serotonergic agent to MAOI's.”

Levy et al. · From the abstract

Names both L-Tryptophan and Phenelzine in its title.

Case report of a toxic reaction from a combination of tryptophan and phenelzine.

The American journal of psychiatry · 1984 · PMID 6691495

Case ReportsHuman subjects

“The addition of tryptophan to a monoamine oxidase inhibitor (MAOI) has been recommended for patients failing to respond to an MAOI alone. The authors report acute behavioral and neurologic toxicity immediately after tryptophan administration in a patient taking phenelzine.”

Thomas et al. · From the abstract

Names both L-Tryptophan and Phenelzine in its title.

Uptake of 5-hydroxytryptamine in the catecholamine containing areas of the hypothalamus of the rat after treatment with phenelzine and tryptophan.

British journal of pharmacology · 1981 · PMID 7284694

Animal study

“1 Uptake of 5-hydroxytryptamine in the catecholamine containing nerve endings of the hypothalamus in the rat brain was found after intraperitoneal injection of phenelzine sulphate (25 mg/kg) and tryptophan (100 and 400 mg/kg). 2 The results were obtained by fluorescence microscopy and microspectrofluorimetry.”

Arbuthnott et al. · From the abstract

Names both L-Tryptophan and Phenelzine in its title.

Limitations

What this evidence cannot tell you.

Search-based evidence indexes have real limits, and it is worth being explicit about them:

NutriStack

Track what you actually take.

NutriStack is a free iPhone app for organising a supplement routine: what you take, when, and what the published record says about it. Its exploratory interaction checker covers L-Tryptophan, Phenelzine, and several hundred other substances.

The checker is a research and organisation tool, not a clinical decision aid, and its per-pair assessments are excluded from search until they pass claim-level review.

NutriStack is an informational and organizational tool, not a medical service, and not a substitute for professional advice. Always consult a qualified healthcare professional before starting, stopping, or changing any supplement or medication.