Hypersensitivity of meperidine.
Centralgin is contraindicated in patients who are receiving monoamine oxidase (MAO) inhibitors or those who have
recently received such agents. Therapeutic doses of meperidine have occasionally precipitated unpredictable, severe,
and occasionally fatal reactions in patients who have received such agents within 14 days. The mechanism of these
reactions is unclear, but may be related to a preexisting hyperphenylalaninemia. Some have been characterized by
coma, severe respiratory depression, cyanosis, and hypotension, and have resembled the syndrome of acute narcotic
overdose. In other reactions the predominant manifestations have been hyperexcitability, convulsions, tachycardia,
hyperpyrexia, and hypertension. Although it is not known that other narcotics are free of the risk of such reactions,
virtually all of the reported reactions have occurred with meperidine. If a narcotic is needed in such patients, a
sensitivity test should be performed in which repeated, small, incremental doses of morphine are administered over
the course of several hours while the patients condition and vital signs are under careful observation. (Intravenous
hydrocortisone or prednisolone have been used to treat severe reactions, with the addition of intravenous
chlorpromazine in those cases exhibiting hypertension and hyperpyrexia. The usefulness and safety of narcotic
antagonists in the treatment of these reactions is unknown.)
Solutions of meperidine and barbiturates are chemically incompatible.