Each year, millions of Americans safely undergo surgery under anesthesia.

Anesthesia is a combination of medicines given during medical procedures and surgeries to block pain. Using a person's specific medical information as a guide, anesthesiologists are able to select the appropriate type and amount of anesthetic needed.

If you'll be undergoing anesthesia, it's important to be honest with your anesthesiologist about your medical history and certain lifestyle choices. Here's what to discuss with your anesthesiologist before a procedure or surgery:

• Any medications or supplements you take. Bring along your prescription and nonprescription drugs and supplements to show your anesthesiologist. Or if it's easier, take pictures of the labels.

  You may be instructed to temporarily stop taking some medications if they're known to interact with anesthesia or increase surgical risks.

• Smoking exposure. Your anesthesiologist needs to know if you're a current or former smoker — or if you experience health effects, like coughing or asthma, from secondhand smoke.

  Smoking brings increased surgical risks, so anesthesiologists will plan an anesthetic that decreases your risk as much as possible during and after surgery. Stop smoking prior to your surgery at the earliest opportunity.

• Marijuana and alcohol use. This can affect the dose of anesthetics required. And marijuana can interact with anesthetic medications.
• Sleep apnea. Snoring can be a sign of obstructive sleep apnea (OSA) — a disorder in which breathing repeatedly stops and starts. Those with OSA may be more prone to surgical complications, and general anesthetics may make OSA worse.
• Health conditions. Health issues, especially those involving the heart, brain or lungs, as well as conditions like diabetes should be shared with your anesthesiologist.
• Anesthesia reactions. Tell your anesthesiologist if you've had reactions or unpleasant side effects, like nausea or vomiting, to anesthesia in the past. He or she will make necessary modifications.