Piperacillin: Not metabolized.Two references consider it safe. Tazobactam: Mainly excreted in unchanged form.

(To be edited, initial data ST OCT 04) Piperacillin: 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. Tazobact: Betalactamase inhibitor (up to 500 mg / 24 h) mainly excreted via the kidneys in unchanged form. Piperacillin: South African list: use. EPI-list: safe. Tazobactam: South African list: no data/avoid.

Uneventful use reported in 2 patients with acute porphyria.