MAO INHIBITORS AND SOYBEANS CAUSE HYPERTENSIVE CRISIS.

The interaction between monoamine oxidase (MAO) inhibitors, drugs widely used for the treatment of depression, and cheeses rich in tyramine is well known -- the result can be a fatal hypertensive crisis. Less well known is the fact that there are other foods that are also rich in tyramine and can have similar interactions with MAO inhibitors. In a letter to JAMA, the author reports a hypertensive crisis in a 41-year-old woman being treated with the MAO inhibitor phenelzine sulfate (Nardil) who ate miso, a soybean-based soup stock commonly used in Oriental cooking. (Soy beans and soy sauce are rich in tyramine.) The resulting hypertensive crisis produced headache and a transient encephalopathy.

The author encourages physicians with patients t…