Carbamazepine | Oxcarbazepine
CBZ is available in the United States as a proprietary product
(Tegretol) marketed for epilepsy by Novartis Pharmaceuticals Corporation
in suspension (100 mg/5 mL), chewable tablets (100 mg),
nonchewable tablets (200 mg), and extended-release (Tegretol XR)
tablets (100-, 200-, and 400-mg) ("Tegretol" 2008).
An additional proprietary extended-release formulation marketed for
epilepsy as Carbatrol (by Shire US Inc.) and for bipolar disorder
as Equetro (by Validus Pharmaceuticals) is available in 100-, 200-,
and 300-mg capsules ("Carbatrol" 2008; "Equetro" 2008).
Intramuscular and depot formulations are not available. CBZ is also
available in generic formulations. Differences have been observed
in the bioavailability of proprietary and generic formulations (Meyer et al. 1992).