Modafinil 200 mg is a prescription medicine indicated to improve wakefulness in adults with excessive sleepiness associated with narcolepsy, obstructive sleep apnea, or shift work disorder. In obstructive sleep apnea, modafinil treats excessive sleepiness and does not treat the underlying airway obstruction. Modafinil tablets are available in 100 mg and 200 mg strengths and carry important warnings concerning serious skin reactions, hypersensitivity reactions, psychiatric symptoms, and potential misuse.