Antagonism of imipramine induced fatal hyperpyrexia in MAO inhibitor treated rabbits.

Extensive use of monoamine oxidase inhibitors and imipramine in psychiatric practice has revealed serious toxic reactions. It has been observed that combination of monoamine oxidase inhibitor and imipramine produces a symptom complex characterized by hyperexcitement, motor restlessness and hyperpyrexia (1-6). Furthermore, hypertensive crisis, subarachnoid haemorrhage and pulmonary oedema has been reported to occur in patients who were maintained on monoamine oxidase inhibitor and took cheese or broad beans (7 , 8). High contents of tyramine in cheese and 3-4 dihydroxyphenylalanine (dopa) in broad beans have been sug gested to be responsible for the above mentioned serious side effects. Since it is known that in MAO inhibitor pretreated animals administration of both, tyramine and dopa increase circulating catecholamine content