Major Pharmaceuticals Carbidopa and Levodopa 25 mg/100 mg Unit Dose Tablets are a medication used to treat symptoms of Parkinson's disease, such as tremors, stiffness, and trouble with movement and coordination. The tablets come in individual unit dose packs, each containing 10 tablets. Carbidopa and levodopa work together to increase the levels of dopamine in the brain, a chemical that is lacking in people with Parkinson's disease. This helps to improve symptoms and overall functioning. These tablets are distributed by Major Pharmaceuticals, a U.S.-based company that provides generic and over-the-counter medications.