Not metabolized.Two references state non- porphyrinogenicity.

(To be edited, initial data ST OCT 04) Broadspectrum penicillin used parenterally (4 g x 3) in septicemia where Pseudomonas infection is verified or suspected. Excreted in bile and by the kidneys in unchanged form. No data pointing to CYP interaction. EPI-list: safe. South African list: use.

Uneventful use reported in 2 patients with acute porphyria.