Concepts

Reference
J.F.M. Nouws et al: Comparative plasma Ampicillin levels and bioavailability of five parenteral Ampicillin formulations in ruminant calves.

Significance Route of administration and dose form affect the performance (clinical effect) of drug products. Ampicillin sodium is labeled for intravenous and intramuscular use. Ampicillin trihydrate is labeled for intramuscular use only. Your choice of drugs should be based on the performance characteristics you desire in addition to the labeled route and the price of the penicillin product. This exercise demonstrates that, for Ampicillin at least, drug concentrations may be affected more by dose form than by route of administration.