Substrate of Cyps 2D6, 3A4 and 1A2. Water soluble drug, thus probably devoid of capacity for significant PXR-activation and subsequent Cyp-induction. Demonstrated in vitro not to be a Cyp-inhibitor or Cyp-inducer. The common side effect of constipation may worsen pre-existing porphyria-induced constipation in the patient.

Quinuclinidinyl-benz-isokinoline. Two cyclic tertiary amine functions in the molecule.

Palonosetron is used for prevention of nausea in chemotherapy. It is a potent selective 5-HT receptor antagonist inhibiting reflexogenic nausea caused by 5-OH tryptamine. Confounding side effects: constipation, diarrhoea.

Metabolized mainly by Cyp 2D6, and to a minor extent by Cyp 3A4 and 1A2. In-vitro studies demonstrate abscence of capacity for Cyp-inhibition or induction.