A comparative study of talampicillin and ampicillin in general practice.

Talampicillin hydrochloride, the phthalidyl ester of ampicillin, when given in a dosage containing the equivalent of 125 mg of ampicillin four times daily for six days to general practice patients, has proved to be as effective, both clinically and bacteriologically, as 250 mg of ampicillin given four times daily for six days. Although the over-all incidence of side-effects was similar with both preparations, diarrhoea was significantly reduced in talampicillin-treated patients. Possible reasons for this are discussed. Talampicillin therefore offers certain advantages over ampicillin in producing effectiveness equivalent to that of ampicillin at a lower dosage level with a reduced incidence of diarrhoea.