Eosinophilia‐myalgia syndrome due to l‐tryptophan ingestion: report of four cases and review of the Maryland experience

Eosinophilia-myalgia syndrome (EMS) is a recently described clinical entity that has been ascribed to taking over-the-counter preparations of the amino acid L-tryptophan. We describe 4 patients with EMS, 3 of whom presented with eosinophilic fasciitis, and we review the epidemiology of EMS reported in Maryland and discuss the possible pathophysiology of the disease. EMS should be considered in the differential diagnosis of severe myalgia, eosinophilia, and eosinophilic fasciitis.