What to Know Before You Get Anesthesia

Medically Reviewed by Jennifer Robinson, MD on September 20, 2023
Written by WebMD Editorial Contributors
5 min read

Are you about to have a medical procedure that requires anesthesia, the medicine you get so you don't feel pain? You probably have some questions about how it works and what to expect when you get it.

It comes in three forms:

  • General anesthesia: Makes you unconscious so you can’t feel pain. You can get this type of medicine as a gas or vapor that you breathe in through a mask or tube. Or you can get it through a needle into a vein.
  • Regional anesthesia: Numbs the general area of your body where the surgery will be done. The doctor will inject medicine into a clump of nerves. One well-known type is an epidural. You get it in your spinal cord to numb your lower body. Sometimes you can get both regional anesthesia and a sedative through an IV. This is called "twilight sleep." You aren’t fully asleep, but you’re not fully awake, either.
  • Local anesthesia: The doctor numbs a much smaller area of your body where the procedure will be done. They can inject the medicine or rub it onto your skin. It’s used for minor procedures like removing a mole.

A doctor called an anesthesiologist or health professional called a nurse anesthetist will give you general and regional anesthesia. They’ll also check your breathing, heart rate, and other vital functions while you're under.

You'll meet with your anesthesiologist before the procedure. They’ll ask about your medical history and what medicines you take.

Let them know if you:

  • Have any allergies
  • Have a health condition, including high blood pressure, heart problems, diabetes, liver or kidney disease, sleep apnea, or thyroid disease
  • Have asthma, COPD, bronchitis, or other breathing problems
  • Smoke, drink alcohol, or take street drugs
  • Take NSAIDs, steroid medicines, insulin, or oral hypoglycemics
  • Have numbness or weakness in your arms or legs
  • Have bleeding problems
  • Are pregnant
  • Reacted to anesthesia in the past

Ask your anesthesia doctor any questions you have about your surgery or the medicine you'll get. Make sure that you're comfortable with your anesthesia team and that you know what to expect before your operation.

If you're getting general anesthesia, the doctor will probably ask you to stop 6 to 8 hours before the procedure. Many will tell you not to eat or drink anything after midnight on the night before your operation. That's because anesthesia makes you sleepy and relaxed. The muscles of your stomach and throat also relax, which can cause food to back up and get into your lungs while you’re out. An empty stomach helps prevent this.

If you take medicine every day, ask your doctor if you can take it with a small sip of water on the day of surgery. Your doctor may tell you not to use some of your medications a few days or more before your surgery because they don't mix well with the drugs used for anesthesia. You may also need to stop certain meds because they can make you bleed more during the operation, like blood thinners such as clopidogrel (Plavix) and warfarin(Coumadin), and NSAIDs like aspirin and ibuprofen.

Blood pressure drugs and reflux medicines should be OK to take, but ask your doctor to know for sure.

Some herbal supplements can react with your anesthesia, increase bleeding, or affect your blood pressure during surgery. They include supplements like:

  • Black cohosh
  • Feverfew
  • Garlic
  • Ginger
  • Ginkgo
  • Ginseng
  • Kava
  • St. John's wort
  • Valerian

Tell your doctor about every supplement you take and get their opinion on whether you need to stop using it.

An anesthesiologist or nurse anesthetist will be with you during your surgery. They’ll give you medicine to keep you asleep for the whole procedure. They’ll also keep track of your vital signs like heart rate, body temperature, breathing, and blood pressure.

The length of time you are unconscious depends on how long your surgery lasts. Once it’s done, you’ll stop getting the anesthesia. You'll wake up in a recovery room.

General anesthesia isn’t like being asleep. You won't have dreams that you can remember. You shouldn't remember anything -- including the procedure.

After your surgery, you'll go to a recovery room to wake up. Nurses will monitor your heart rate, breathing, and other vital signs for about 30 minutes.

As you come out of the anesthesia, you might feel groggy and confused. The drugs’ effects can take a few hours to fully wear off.

You may have some side effects, but most are minor and temporary. It depends on which type of anesthesia you get.

Side effects from general anesthesia include:

Side effects from regional anesthesia include:

How long you stay in the hospital depends on the type of procedure you had. Some procedures require an overnight hospital stay or longer. If you had a same-day surgery, you should be able to go home 1 to 4 hours afterward.

 If you get local anesthesia, which just numbs part of your body during surgery, you may be able to drive yourself home. If you have general anesthesia, you will need to arrange ahead of time for someone to drive you home. You won't be able to hit the road for 24 hours after the anesthesia. The same is true if you get some kind of "sedation" medicine, which relaxes you. Arrange for a friend or family member to take you home. And have someone stay with you for the first day while you recover at home.

If you go home on the same day as your procedure, you’ll probably notice some mild side effects until the anesthesia fully wears off:

You might also have side effects from the surgery itself. Try to take it easy for at least a day after your procedure.