Eosinophilia-myalgia syndrome. Results of national surveillance

JAMA. 1990 Oct 3;264(13):1698-703.


Eosinophilia-myalgia syndrome, a newly recognized disorder that occurred in epidemic proportions during 1989, is associated with ingestion of manufactured tryptophan. A case is defined by debilitating myalgias and absolute eosinophilia greater than or equal to 1.0 x 10(9) cells/L. As of July 10, 1990, a total of 1531 cases had been reported nationwide, including 27 deaths. The highest rates of reported illness are concentrated in the western states, 68% are non-Hispanic white women aged 35 years and older, and data on associated clinical findings suggest a multisystemic disorder. The most frequent features include arthralgia (73%), rash (60%), cough or dyspnea (59%), peripheral edema (59%), elevated aldolase level (46%), and elevations in the results of liver function tests (43%). Neuropathy or neuritis, resulting in paralysis and death in some patients, was seen in 27%, and chest roentgenogram abnormalities were noted in 21% of those tested. Ninety-one percent reported onset of symptoms during or after May 1989, and 97% reported having taken tryptophan before the onset of symptoms. Since the recall of over-the-counter preparations of tryptophan in November 1989, the number of new cases of this potentially fatal disorder has fallen dramatically.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Child
  • Child, Preschool
  • Disease Outbreaks
  • Eosinophilia / chemically induced
  • Eosinophilia / epidemiology*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Muscles*
  • Pain / chemically induced
  • Pain / epidemiology*
  • Population Surveillance
  • Seasons
  • Syndrome
  • Tryptophan / adverse effects*
  • United States / epidemiology


  • Tryptophan