L-TRYPTOPHAN AND THE EOSINOPHILIA-MYALGIA-SYNDROME - A CLINICAL AND LABORATORY STUDY

Case notes of 202 patients who were prescribed a single brand of L-try ptophan (Optimax(R), manufactured by Merck) between January 1987 and D ecember 1991 were examined. Fourteen patients' notes indicated that th ey had clinical or laboratory findings suggestive of a diagnosis of eo sinophilia-myalgia syndrome (EMS). However, results of clinical examin ation and measurement of serum aldolase, total eosinophil count and an tinuclear antibodies did not support the diagnosis of EMS in any of th e 14 patients. Although a further study of 50 consecutive patients on L-tryptophan at the time of the investigation revealed that 5 had mild eosinophilia, none reached the criteria for EMS established by the US Centers for Disease Control and Prevention.