Dangerous Potentiation of Meperidine Hydrochloride by Pargyline Hydrochloride

INTEREST IN the role of monoamine oxidase (MAO) inhibitors in the treatment of hypertensive disease has been stimulated by the widely noted observation that therapy with potent monoamine oxidase inhibitors produces marked orthostatic hypotension. Originally a troublesome side reaction, this property has since been utilized in the treatment of hypertension. Recently, the introduction of a new drug, pargyline hydrochloride (Eutonyl), with powerful MAO inhibiting properties and antihypertensive effects, has been used as a therapeutic agent in the treatment of hypertension.

Little known is the fact that the effects of meperidine (Demerol) hydrochloride are markedly potentiated when administered to patients concurrently taking MAO inhibitors. To my knowledge, this has not been reported in the American literature with the exception of a precaution concerning the drug,¹ although it has been discussed by the British.^2-6 It is felt that a timely warning of the danger of meperidine administration to patients being