[17][18] Contraindications include:[10][11][19] Tyramine is a biogenic amine produced as a (generally undesirable) byproduct during the fermentation of certain tyrosine-rich foods.

Individuals sensitive to tyramine-induced hypertension may experience an uncomfortable, yet fleeting, increase in blood pressure after ingesting relatively small amounts of tyramine.

[20][19][21] Advances in food safety standards in most nations, as well as the widespread use of starter-cultures shown to result in undetectable to low levels of tyramine in fermented products has rendered concerns of serious hypertensive crises rare in those consuming a modern diet.

Since tyramine-producing microbes also produce compounds to which humans have a natural aversion, disposal of any questionable food—particularly meats—should be sufficient to avoid hypertensive crises.

[17] Pharmacokinetic interactions with anesthetics are unlikely, given that tranylcypromine is a high-affinity substrate for CYP2A6 and does not inhibit CYP enzymes at therapeutic concentrations.

[10][26][17] It is thought that higher doses have more amphetamine-like effects and abuse is promoted by the fast onset and short half-life of tranylcypromine.

Tranylcypromine inhibits this enzyme with an IC50 < 2 μM, thus acting as a small molecule inhibitor of histone demethylation with an effect to derepress the transcriptional activity of BHC110/LSD1 target genes.

Precisely because tranylcypromine was not, like isoniazid and iproniazid, a hydrazine derivative, its clinical interest increased enormously, as it was thought it might have a more acceptable therapeutic index than previous MAOIs.

[34] It was withdrawn from the market in February 1964 due to a number of patient deaths involving hypertensive crises with intracranial bleeding.

[36][37] Tranylcypromine may have neuroprotective properties applicable to the treatment of Parkinson's disease, similar to the MAO-B inhibitors selegiline and rasagiline.

[38][11] As of 2017, only one clinical trial in Parkinsonian patients has been conducted, which found some improvement initially and only slight worsening of symptoms after a 1.5 year followup.