Nonselective monoamine oxidase (MAO) inhibitors are contraindicated for use with Levodopa and Carbidopa. These inhibitors must be discontinued at least two weeks prior to initiating therapy with Levodopa and Carbidopa. Levodopa and Carbidopa may be administered concomitantly with the manufacturer's recommended dose of an MAO inhibitor with selectivity for MAO type B (e.g., selegiline HCl) (see Interactions). Levodopa and Carbidopa is contraindicated in patients with known hypersensitivity to any component of this drug, and in patients with narrow-angle glaucoma. Because levodopa may activate a malignant melanoma, Levodopa and Carbidopa should not be used in patients with suspicious, undiagnosed skin lesions or a history of melanoma.