Line art icon of a pharmacist  Ask the Pharmacist

Your Express Scripts Canada pharmacist has a wealth of knowledge on a wide range of health topics. If you have a question about your health or medication, chances are, your Express Scripts Canada pharmacist knows the answer.

Q: How long does alcohol stay in your system, and how can it affect prescription medications?

When people ask this question, they are often wondering how long after they drink alcohol they’ll continue to feel the effects. They may also want to understand how long alcohol can be detected in their blood, in the context of a breathalyzer test and legal limits to alcohol levels when they’re driving.

On a basic level, alcohol enters your body through your digestive system – your stomach and small intestine – and from there, is absorbed into your bloodstream. Your blood alcohol concentration is the percentage of pure alcohol in your blood and this is measured by a breathalyzer.

Many different factors can have an impact on how quickly alcohol enters your bloodstream and how long it remains there – affecting your blood alcohol concentration.

The organization Mothers Against Drunk Driving (MADD) Canada explains that some of the factors affecting how quickly your Blood Alcohol Concentration rises and drops include your body type, weight and food intake at the time of drinking.

For example, when it comes to body type and weight – If you are lighter, you have less blood, and your blood alcohol concentration will be higher than a heavier person who drinks the same amount. Also, if you have a lot of body fat and you drink as much alcohol as someone who is muscular, your blood alcohol concentration will be higher.

If you have eaten more food and your stomach is fuller, it takes longer for the alcohol to be absorbed into your blood.

It is vital to remember that there can be serious health consequences to consuming alcohol. Over time, excessive alcohol use can lead to the development of chronic diseases and other serious conditions including:

  • high blood pressure,
  • heart disease,
  • stroke and
  • liver disease.  

If you are already taking medications, it is important for you to understand that many medications react negatively with alcohol. In some cases, drinking alcohol can decrease the effectiveness of medications. Another risk is that drinking will make you more likely to experience side effects from your medications and can harm your health. 

If you are taking medications, check the product labels for alcohol warnings and make sure you consult your doctor or pharmacist before you drink.

Express Scripts Canada pharmacist can help. If you are a patient of ours, we will take the time to help you understand the possible effects of consuming alcohol while you are taking medications.

Until next time, this has been Ask the Pharmacist.

I wish you good health.


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