The pharmacokinetics of teicoplanin were studied following a 440 mg intravenous dose in six male volunteers. The levels of the compound were measured in serum, blister fluid and urine. The mean serum level 0.5 h after injection was 44.6 mg/l falling to 3.6 mg/l at 49 h. The elimination half-life of teicoplanin from serum was 34.2 h and the apparent distribution half-life 1.5 h. Penetration into blister fluid was moderately fast, the mean maximum concentration (14.8 mg/l) occurring at 2.7 h, and the mean percentage penetration being 77.4%. Urinary recovery of the drug was 48.3% by 96 h.