Clinical and practitioners' reports on adverse effects of co-trimoxazole.

This study concerns the incidence of side effects occurring in connection with the prescription of co-trimoxazole which, according to the observations of medical practitioners, were suspected of being drug related. It is based on reports from 260 doctors in the Nordbaden/Rheinlandpfalz area between 1981 and 1984, as well as on those from hospital doctors concerning 33,300 in-patients at the Department of Internal Medicine at the University Hospital of Heidelberg from 1980 to 1983. General practitioners' reports: Of 3,739 side effects reported over a three and a half year period, 180 were related to drugs containing co-trimoxazole. Side effects were 3.3 times as frequent with the "forte" dosage as compared to the 80 mg trimethoprim/400 mg sulfamethoxazole preparation. The most frequently cited unwanted reactions concerned the skin (n = 63, of which two were Quincke oedema and three were urticarious reactions) and the gastrointestinal tract (n = 52), as well as disturbance of well being (n = 30). Gastro-intestinal disturbances appeared to occur more frequently after a higher than after a lower dosage. Clinicians' reports: During the period of observation an average of 12.6% of all in-patients were treated with drugs containing co-trimoxazole. The total number of cases of side effects due to this drug amounted to 255. Serious reactions included: two anaphylactic reactions; two thrombocytopenias below 80,000/mm3; and two cases of Lyell's syndrome (one of which could not be confirmed beyond all doubt). Side effects occurred more often after i.v. than after oral application.(ABSTRACT TRUNCATED AT 250 WORDS)