According to WebMD, the time for anesthesia to wear off depends on several factors, including the type of anesthetic, other medications a person may be taking and the body's response to the anesthetics. Anesthesia is given before and during a surgical procedure and is stopped when the procedure is complete.
The effects of anesthesia may last hours after surgery, notes WebMD. Following surgery, a patient may still continue to feel numbness in the area where the anesthetic was administered. Muscle control and coordination may be affected. Cold shivers may be felt upon wakening. Nausea and vomiting are shorter-term symptoms that are treatable.