Pivmecillinam: past, present, and future

Pivmecillinam is the oral prodrug of mecillinam. Following absorption, the pivaloyl ester is hydrolyzed, releasing the active mecillinam into systemic circulation. It is a narrow spectrum amidino(penicillin) antibiotic with activity against the main uropathogens. Pivmecillinam has been used for decades in the Nordic countries as one of the main drugs for uncomplicated urinary tract infection (uUTI) with resistance levels in Escherichia coli remaining around 5%.

A literature search was performed via PubMed during January-February 2026. The review centers on a brief mention of the mechanism of action, resistance mechanisms, pharmacokinetics, pharmacokinetic/pharmacodynamics, adverse effects, and clinical use. Pivmecillinam is stable against many broad-spectrum beta-lactamases increasing its versatility as an empiric antibiotic. The main indication is uUTI, but it is also used for treatment of acute pyelonephritis. The review addresses clinical experience, dose and duration of treatment with suggestions for dosing recommendations. There remains some debate on the ideal dose and duration of treatment. Pivmecillinam can also be used for treatment of some bacterial diarrhea types.

Pivmecillinam can play an important role as empiric and directed treatment for UTIs due to its beneficial antibacterial spectrum against common uropathogens, stability toward beta-lactamases, minor effect on microbiomes and general safety.