Waklert 150mg can keep you awake and aware for 12-15 hours, depending on your metabolism, body weight, and tolerance. Its effects begin within 1 to 2 hours of intake and peak at 6 to 8 hours. Waklert, a wakefulness-promoting drug, is commonly used to treat narcolepsy, shift work disorder, and sleep apnea-related lethargy. It has a longer half-life than modafinil, resulting in greater maintained alertness and fewer crashes. To avoid disrupting sleep, take it in the morning. Always use Waklert as directed and avoid taking it too late in the day.