SPL Set ID: 43ce5061-0830-6f4f-e063-6394a90afc59

Carbidopa and levodopa tablets, USP are a combination of carbidopa and levodopa for the treatment of Parkinson's disease and syndrome. Carbidopa USP, an inhibitor of aromatic amino acid decarboxylation, is a white to creamy white powder, freely soluble in 3N hydrochloric acid, slightly soluble in water and methanol, practically insoluble in alcohol, acetone, ether and chloroform, with a molecular weight of 244.3. It is designated chemically as (—)-L-α-hydrazino-α-methyl-β-(3,4-dihydroxybenzene) propanoic acid monohydrate. Its molecular formula is C 10 H 14 N 2 O 4 •H 2 O, and its structural formula is: Tablet content is expressed in terms of anhydrous carbidopa which has a molecular weight of 226.3. Levodopa USP, an aromatic amino acid, is a white to off-white, crystalline powder, slightly soluble in water, freely soluble in 3N hydrochloric acid, insoluble in alcohol, with a molecular weight of 197.2. It is designated chemically as (—)-L-α-amino-β-(3,4-dihydroxybenzene) propanoic acid. Its molecular formula is C 9 H 11 NO 4 , and its structural formula is: Carbidopa and levodopa is supplied as tablets for oral administration in three strengths: Carbidopa and levodopa tablets USP, 25 mg/100 mg containing 25 mg of carbidopa USP and 100 mg of levodopa USP. Carbidopa and levodopa tablets USP, 10 mg/100 mg containing 10 mg of carbidopa USP and 100 mg of levodopa USP. Carbidopa and levodopa tablets USP, 25 mg/250 mg containing 25 mg of carbidopa USP and 250 mg of levodopa USP. Inactive ingredients are crospovidone, hydroxypropyl cellulose, magnesium stearate, microcrystalline cellulose, and pregelatinized starch (maize). Carbidopa and levodopa tablets USP, 10 mg/100 mg and 25 mg/250 mg also contain FD&C Blue No.2 Aluminum Lake. Carbidopa and levodopa tablets USP, 25 mg/100 mg also contain D&C Yellow No.10. FDA approved dissolution test specifications differ from USP.