[1] A public teaching hospital, Fernand-Widal has medicine, surgery, and obstetric departments and treats a large number of indigent patients[2] including those with drug addictions.

[9][10] The hospital's expertise in the area of drug overdoses has resulted in them treating celebrity or criminal patients, including pop star Dalida in 1967[11] and art dealer Fernand Legros (charged with dealing in forgeries).

[12] Research published in 1991 by doctors at the hospital found that many house-fire survivors may be subsequently poisoned by cyanide released by burning household fabrics.

[13] The hospital's toxicologists are regarded as the world's experts in the management of cases involving the typically fatal ingestion of poisonous Amanita phalloides "death cap" mushrooms.

[14][15][16] The department came to prominence under the leadership of Michel Gaultier, who trained as a forensic pathologist and became head of internal medicine at Fernand-Widal in the 1950s.