Alcohol and surgery: A dangerous combination

People who drink alcoholic beverages are at higher risk of complications during and after surgery. Alcohol consumption can reduce heart and immune system function, prolong bleeding time, and increase the body’s stress response. The less alcohol you drink before surgery, the better. In this video, Dr. Leslie Martin discusses the potential surgical and post-operative risks for people who consume alcohol in the days or weeks leading up to surgery.

Note, this video was recorded prior to January 2023 Canadian guideline update. The report titled Canada's Guidance on Alcohol and Health reflects the most recent data and methods that have evolved since the guidelines were released in 2011.


Learn the answers to the following questions:

2:14 - What is low-risk drinking?

6:01 - What are some of the potential surgical complications?

9:29 - What are some of the potential post-operative risks? 

12:44 - How can you safely reduce alcohol consumption before surgery?

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This work is supported through the McMaster Institute for Research on Aging and funds provided by the Dean and Vice-President, Faculty of Health Sciences at McMaster University.

DISCLAIMER: These summaries are provided for informational purposes only. They are not a substitute for advice from your own health care professional. The summaries may be reproduced for not-for-profit educational purposes only. Any other uses must be approved by the McMaster Optimal Aging Portal (

Many of our Blog Posts were written before the COVID-19 pandemic and thus do not necessarily reflect the latest public health recommendations. While the content of new and old blogs identify activities that support optimal aging, it is important to defer to the most current public health recommendations. Some of the activities suggested within these blogs may need to be modified or avoided altogether to comply with changing public health recommendations. To view the latest updates from the Public Health Agency of Canada, please visit their website.