Substrate of CYP 1A2, 2C19, 2C8, 2C9, 2D6, 3A4 (major enzyme at higher concentrations), 2C19, 2E1. Inhibitor of CYP 3A4 (low potency), 2D6, 2C19, 2C9. References consider it safe for use. Observed not to be porphyrinogenic in long-term treatment of one patient (Sweden).

High-dose neuroleptic (benzodiazepine derivative) used in therapy resistent schizophrenia. Extensively metabolized via CYPs. South African list: use with care French list: use. See Holoryd S et al. Psychotropic drugs in acute…(one case) (PMID: 10511069). Thunell; clinical experience from prolonged treatment (n=1): no porphyric side effects.

Report on uneventful use: One report of uneventful use of clozapine for 2-3 years in female AIP patient with known mutation. Porphyrin excretion low/normal during use. From Dr Salamanca, Madrid.

Uneventful use reported in 1 patient with acute porphyria.