Scheduled for surgery? Say no to alcohol

The Bottom Line

  • You are engaging in “risky drinking” if you consume 3 or more drinks per day, or 21 drinks per week, before having surgery.
  • Intensive approaches that aim to help people quit drinking before surgery may reduce complications and alcohol consumption post-surgery.
  • People who receive these intensive programs may also be more likely to successfully quit drinking by the end of the program. 

If there is ever a time to refrain from drinking alcohol, it’s before you go ‘under the knife’. But why is abstaining so important before surgery? It all comes down to how well you come out on the other side.

Worldwide, the number of people who drink alcohol is decreasing. However, among people who do choose to partake, the amount consumed per person is on the rise (1). Excessive drinking is associated with all sorts of health issues, including liver disease, damage to the pancreas, neurological problems (2-4), cancer, and HIV/AIDS (1). These conditions, alongside other infectious and chronic diseases, intentional injuries (from suicide or violence), and unintentional injuries (from falls, car crashes, drownings, etc.), help contribute to the 3 million global deaths that result from harmful drinking each year (3;5).

Alcohol is not just a concern for long-term health. People who drink multiple alcoholic beverages per day are also at higher risk of complications after surgery (3), such as infection, bleeding, or heart and lung problems (3;6). This is especially true for people who engage in “risky drinking”, which equals 3 standard drinks per day or 21 drinks per week (3). One standard drink is a 12-ounce bottle of beer, a 1.5 ounce shot of hard liquor, or a 5-ounce glass of wine (7).

Why are alcohol and surgery such a bad combination? Well, alcohol consumption can reduce heart (3;8) and immune system function, prolong bleeding time, and increase the body’s stress response (3;9). All of which are risk factors for developing complications following surgery (3).

What the research tells us

A recent systematic review looked at the effect of intensive approaches—included patient education, treatment of withdrawal, medication to prevent relapse—that aimed to help “risky drinkers” scheduled for surgery to quit drinking before surgery. These surgeries were either planned in advance for non-emergency conditions (e.g., hip replacements), or were for emergency conditions requiring relatively speedy care (e.g., serious ankle injuries). For pre-planned surgeries, intensive programs took place in the weeks leading up to the surgery, while in emergency cases, the programs took place right before or after the surgery.

The review found that intensive approaches occurring over 4 to 8 weeks may reduce post-surgery complications, such as the need for a second surgery, issues around the wound, or heart and lung-related problems. It also appeared that these intensive programs may increase the number of people who successfully quit drinking by the end of the program, while potentially reducing the amount of alcohol consumed in those that continued to drink following surgery. Unfortunately, there was not enough information to determine how these intensive approaches impacted length of hospital stays or the risk of death from complications due to surgery. Despite the promising results, more high-quality research on this topic area is needed. Future research should include a greater number of participants, be conducted in different settings (e.g., countries), and evaluate strategies other than intensive approaches (3).

The bottom line is, the less alcohol you drink before surgery, the better. Kicking alcohol to the curb may help maximize your chance of a speedy, complication-free recovery.

Interested in learning about more ways to reduce the risk of post-surgery complications? Check out Scheduled for surgery? Quit smoking to reduce the risk of complications.

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  1. World Health Organization. Global status report on alcohol and health 2018. Geneva (CH): World Health Organization; 2018. 472 p. Available from  
  2. Mayo Clinic. Alcohol use disorder. [Internet] 2018. [cited February 2019]. Available from 
  3. Engholm JW, Pedersen B, Møller AM, et al. Perioperative alcohol cessation intervention for postoperative complications. Cochrane Database Syst Rev. 2018; (11):CD008343. doi: 10.1002/14651858.CD008343.pub3. 
  4. Spies C, Tønnesen H, Andreasson S, et al. Perioperative morbidity and mortality in chronic alcoholic patients. Alcohol Clin Exp Res. 2001; 25(5):164–170.
  5. World Health Organization. Global status report on alcohol and health 2014. Geneva (CH): World Health Organization; 2014. 392 p. Available from 
  6. Tønnesen H. Alcohol abuse and postoperative morbidity. Dan Med Bull. 2003; 50(2):139–160.
  7. Butt P, Beirness D, Gliksman L, et al. Alcohol and health in Canada: A summary of evidence and guidelines for low-risk drinking. [Internet] 2011. [cited February 2019]. Available from 
  8. Tønnesen H, Petersen KR, Højgaard L, et al. Postoperative morbidity among symptom-free alcohol misusers. Lancet. 1992; 340(8815):334-337. 
  9. Tønnesen H, Kehlet H. Preoperative alcoholism and postoperative morbidity. Br J Surg. 1999; 86(7):869–874. 

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