Klonopin, a benzodiazepine, is available as scored tablets with a K-shaped perforation containing 0.5 mg of clonazepam and unscored tablets with a K-shaped perforation containing 1 mg or 2 mg of clonazepam. Each tablet also contains lactose, magnesium stearate, microcrystalline cellulose and corn starch, with the following colorants: 0.5 mg—FD&C Yellow No. 6 Lake; 1 mg—FD&C Blue No. 1 Lake and FD&C Blue No. 2 Lake.
Chemically, clonazepam is 5-(2-chlorophenyl)-1,3-dihydro-7-nitro-2H-1,4-benzodiazepin-2-one. It is a light yellow crystalline powder. It has a molecular weight of 315.72 and the following structural formula: