“How long does vomiting last after anesthesia?”

You may not have any vomiting at all. This often depends on the type of surgery and the post-operative medications given for pain. Opiate-based medications given post-operatively may cause nausea unrelated to the anesthesia. Everybody is different in the amount of side effects. There's been some evidence in the past that people that are prone to motion sickness may get more post-operative nausea. One of the biggest causes of post-operative nausea is caffeine withdrawal if you drink more than two cups of coffee a day or a lot of colas or teas or energy drinks. If you do it is suggested to taper them down over the course of a week preoperatively. It is important to be well hydrated. Drink lots of clear fluids such as water or clear sports drinks, up to the time that you're given in your instructions before surgery. Anesthesiologists routinely give anti-nausea medication as part of the anesthesia cocktail of drugs. Propofol used for anesthesia also tends to decrease nausea on its own.
Best wishes.

There are anesthetic protocols which can minimize the risk of nausea and vomiting after anesthesia. There are also numerous medications which can be given to try to prevent nausea and vomiting. In addition, techniques like spinal anesthesia or peripheral nerve blocks can reduce the risk. Be sure to discuss this with your anesthesia provider and surgeon to consider the alternatives. Good luck!

Can be short lived or extended, or none at all. There is no exact answer. Anesthesiologists take measures to prevent it as much as possible.

Most people, the vomiting does not last long at all. The incidence is very low. Usually, you are given anti nausea meds before the surgery so that you don't wake up vomiting. You vomit persistently if you are one of those people who have a very sensitive chemo receptor trigger zone.

Nausea and vomiting after a General Anesthetic can last anywhere from immediately after surgery in the recovery room to 24 hrs out. If the patient requires a fair amount of narcotics after their surgery this can exasperate the symptoms and may extend those symptoms even beyond that window to 72 hrs or more. The incidence is typically higher in women more than men and in younger patients then the elderly. There are more advanced medications now used to help mitigate these symptoms which have improved and reduced the numbers of patients with post op nausea and vomiting but nothing can actually prevent it from happening altogether.