Anesthesiologist explains why it is advised to avoid alcohol before surgery, shares 4 ways it affects anesthesia

You might think it's harmless to drink a glass of wine the night before surgery - because, nerves, right? However, there is a reason doctors advise against it.

Have you ever wondered why doctors insist you avoid alcohol before surgery? While it may seem harmless to have a drink the night before, alcohol can dramatically interfere with how anesthetic drugs work - making their effects unpredictable and potentially dangerous. Even small amounts can alter your sedation levels, affect your blood pressure, and increase your risk of complications in the operating room. That’s why full honesty with your anesthesiologist is crucial, especially about alcohol or any other substances you’ve taken.

Doctors advise against drinking alcohol before going for surgery. (Unsplash)

Dr Kunal Sood, an anesthesiologist and interventional pain medicine specialist, has explained why medical guidelines strongly advise avoiding alcohol before surgery. In an Instagram video posted on November 30, the anesthesiologist outlines how alcohol interacts with anesthetic drugs and highlights why full disclosure is essential.

Higher dosage requirement

According to Dr Sood, alcohol and anesthetic drugs operate on similar central nervous system pathways, and hence having alcohol in the system can dampen anesthetic effects. He explains, “When alcohol is still in the system, it can blunt the effect of standard doses, meaning the anesthesiologist may need more medication to achieve adequate sedation. Chronic use further alters liver enzymes and receptor sensitivity, making responses less predictable.”

Less predictable sedation

Having alcohol in your system complicates things for the anesthesiologist, as drug responses can vary widely - and intoxication can even lower the amount of anaesthesia required. Dr Sood explains, “Acute intoxication can actually lower anesthetic requirements, increasing the risk of oversedation, respiratory depression and aspiration. Alcohol also weakens airway reflexes and slows gastric emptying, raising airway-management risks during induction.”

Faster blood pressure drops

According to the anesthesiologist, alcohol causes vasodilation and a drop in blood pressure, mirroring the physiological effects of anesthesia. He highlights, “Since anesthesia also lowers blood pressure, combining the two can lead to a more rapid and severe drop once the patient is under. Chronic alcohol use may worsen cardiac function and increase arrhythmia risk.”

Bleeding and healing concerns

Alcohol impairs the body’s healing response and weakens immunity, which can increase bleeding risks during surgery and hinder recovery afterwards. Dr Sood elaborates, “Alcohol impairs platelet function and coagulation pathways and weakens immune response and collagen synthesis. This increases intraoperative bleeding risk and slows postoperative healing, raising the chance of infection or wound issues.”

Why disclosure matters

Dr Sood emphasises the importance of keeping your anesthesiologist in the loop about your use of alcohol and other substances, as anesthetic dosages must be adjusted accordingly. He notes, “Knowing about alcohol use within 24 hours helps anesthesia teams adjust dosing, choose safer induction strategies, and reduce complications. Most guidelines recommend avoiding alcohol for at least 24-48 hours before surgery.”

Note to readers: This article is for informational purposes only and not a substitute for professional medical advice. It is based on user-generated content from social media. HT.com has not independently verified the claims and does not endorse them.