Drug induced pleurisy is often a diagnosis of elimination because the clinical presentation, paraclinical features and anatomicopathological aspect are relatively non-specific. The pleural effusions are typically chronic and somewhat torpid, most often bilateral but may be unilateral. Two types of lesion are found: effusion or thickening and these may be associated. The peculiarity of these pleural diseases are the frequent coexistence of accompanying signs: for example pulmonary, cutaneous, ocular, hepatic, peritoneal, pericardial as well as evidence of inflammation and depending on the medicaments hypereosinophilia, cytolysis, cholestasis or antinuclear antibodies. Anatomicopathogically there is dense fibrosis which is diffuse, pauci-cellular and with little inflammation. The progress is variable according to the drug either going on to complete regression on the cessation of the medication or the persistence of a degree of pleural thickening. The causative drugs are essentially the derivatives of Ergotamine and amongst others bromocryptine and dantrolene.