Effect of Tranylcypromine on the Blood Pressure Response of Tyramine

Abstract

THERE has lately been a growing awareness of an association between hypertensive crises, death and monoamine oxidase inhibitors^1,2. Tranylcypromine has been involved in a number of cases, producing intracranial bleeding, sometimes fatal, in patients who had exhibited paradoxical hypertension and severe headache^3,4. Some reports have suggested that the ingestion of cheese by patients undergoing tranylcypromine treatment may give rise to hypertensive crises^5–7. Asatoor⁸ has shown that certain types of cheese contain amines such as β-phenyl-ethylamine, tryptamine and tyramine. According to these findings, tyramine appears to be one of the amines present in sufficient quantity to be pharmacologically active. It therefore seems possible that ingestion of cheese containing significant amounts of tyramine may play an important part or may be the most important factor in many cases of hypertensive crisis associated with tranyl-cypromine therapy.