N03AE01 - Clonazepam

Probably not porphyrinogenic

Rationale

Extensively CYP3A4 metabolised. Conflicting references. Some clinical experience of non-porphyrinogenicity.

Chemical description

Benzodiazepine derivative used in attacks of epilepsy. Its effect is based on enhancement of normal GABA transmission. Extensively metabolized via CYP3A4, the main metabolite being 7-amino-clonazepam.

Personal communication

Used in porphyria ward (Sweden). Andersson C, patient inquiry: used without ill effects (n=2). Peters: According to our experience probably not porphyrinogenic.

IPNet drug reports

Uneventful use reported in 16 patients with acute porphyria.

Similar drugs

Explore alternative drugs in similar therapeutic classes N03A / N03AE or go back.

References

#	Citation details	PubMed ID
1.	[Acute intermittent porphyria associated with epilepsy in a child: diagnostic and therapeutic difficulties]. Chaix Y, Gencourt C, et al. Arch Pediatr. 1997 Oct; 4(10):971-4.	9436495
2.	Seizure management and hepatic porphyrias. Reynolds NC. Neurology. 1982 Dec; 32(12):1409-10.	6890655
3.	Acute intermittent porphyria and epilepsy: safety of clonazepam. Suzuki A, Aso K, et al. Epilepsia. 1992; 33(1):108-11.	1733741
Porphyria Drug Lists
4.	Australian List Australian Porphyria Association No longer maintained
5.	French List Centre Français des Porphyries
6.	EPI List European Porphyria Initiative No longer maintained
7.	South African List Porphyria South Africa No longer maintained