Modalert and Modvigil are brand names associated with modafinil, a prescription medicine used to promote wakefulness in certain sleep-related disorders. When comparing Modalert vs Modvigil, the active ingredient is an important consideration, although products can differ in manufacturer, formulation, availability, and regulatory status.Modafinil is commonly prescribed for conditions such as narcolepsy, obstructive sleep apnea-related excessive sleepiness, and shift work sleep disorder.