How long it takes to wake up from gastric lavage after taking sleeping pills cannot be generalized and is related to the type of sleeping pills taken, the dose of the drug, the duration and stay of the drug in the stomach, and the metabolic ability of the patient. If the patient has taken sleeping pills for a relatively long time, beyond 4-8 hours after gastric lavage, it takes a relatively long time to wake up, usually 12 hours before the patient can gradually wake up. If the patient takes a small amount of sleeping pills and the gastric lavage is performed within 4 hours, he can wake up within 8 hours. If he takes a small amount of sleeping pills, the patient is in good health and the gastric lavage is relatively thorough, he can wake up within 2 hours.