Metformin and Alcohol: Are They Safe to Mix?

By Craig Sorkin, DNP, APN
Medically reviewed checkmarkMedically reviewed
July 11, 2022

Metformin is a prescription medication taken to treat type 2 diabetes.

If you are an adult and take metformin for whatever diagnosis, chances are, you may occasionally desire an alcoholic drink.

However, doing so may have risks, especially if you have kidney or liver problems or your glucose levels are not in range. 

Talk to your healthcare provider before consuming alcohol while taking metformin.

This article will also help you understand the possible risks.

First we’ll explore the potential interactions between metformin and alcohol.

Then we’ll discuss the precautions and risks of this combination.

We’ll also cover metformin side effects and when you should see a medical provider about drinking while on this medication.

Metformin and Alcohol: Is It Safe to Mix?

Not everyone who takes metformin needs to entirely avoid alcohol.

There are two important factors to consider:

  • Alcohol can worsen diabetes control. Even if your diabetes is well managed, consuming too much alcohol can lead to problems balancing glucose. Even one episode of binge drinking can worsen insulin resistance. Most alcohol is based upon carbohydrates. 
  • Alcohol increases the risk of severe side effects. Metformin is generally safe, but in rare cases, lactic acid builds up because too much metformin stays in the body. This can lead to a life-threatening condition known as lactic acidosis. If you binge drink or regularly drink alcohol, it can increase this risk because alcohol can change the way that the liver metabolizes metformin and could increase the concentration of the drug in your body.

Drinking alcohol in moderation (no more than two drinks per day for people assigned male at birth and no more than one drink per day for people assigned female at birth) while taking metformin is likely safe as long as you do not have other risk factors.

However, excessive alcohol use should be avoided at all cost. 

Medical providers will most likely screen you for your alcohol consumption prior to initially prescribing the medication. 

Have questions about Metformin? Chat with a provider through K Health.

Get Started

Alcohol Interaction Risks

Alcohol changes the way that the body breaks down most medications.

How does alcohol interact with metformin?

Metformin works to balance blood glucose levels by preventing the liver from making glucose.

As a byproduct of this, lactic acid can increase in the bloodstream.

As long as you do not have kidney or liver problems and you do not heavily drink alcohol, this is not problematic.

However, drinking alcohol also causes blood levels of lactic acid to rise.

Combining alcohol with metformin could result in too much lactic acid, causing lactic acidosis.

Beyond that, alcohol can worsen less serious side effects of metformin such as nausea, vomiting, and diarrhea.

Precaution and Risks

While metformin is generally safe and well-tolerated long term, it comes with potential complications.

The most common long-term effect of metformin is the risk of developing vitamin B12 deficiency, which can lead to anemia.

Metformin also has many possible drug interactions, including:

  • Other diabetes medications
  • Glycopyrrolate
  • Iodinated contrast agents
  • Lamotrigine
  • Bupropion (Wellbutrin, Aplenzin)
  • Carbonic anhydrase inhibitors
  • Cephalexin
  • Prothionamide
  • Pegvisomant
  • Cimetidine
  • Dolutegravir
  • Androgens
  • Alpha-lipoic acid
  • Selective serotonin reuptake inhibitors (SSRIs)
  • Quinolones
  • Ranolazine
  • Topiramate
  • Salicylates

Metformin may be too risky for individuals with certain health conditions such as:

If you take metformin, you may be asked to temporarily stop taking it before procedures such as:

  • Surgery
  • Radiology tests with iodine contrast

Who is more at risk when mixing alcohol and metformin?

Some people may experience more side effects when they consume alcohol while taking metformin.

People at higher risk include:

  • Adults over age 65
  • People assigned female at birth
  • People who have liver problems or disorders
  • People who have kidney disease or kidney problems

Side effects and complications

Common side effects of metformin include:

More serious complications include:

  • Vitamin B12 deficiency
  • Anemia
  • Hypoglycemia
  • Lactic acidosis

Signs of lactic acidosis are a medical emergency.

If you or someone you care for takes metformin and shows the following signs, call 911 immediately:

Have questions about Metformin? Chat with a provider through K Health.

Get Started

When to See a Medical Provider

Talk to a medical provider if you take metformin and want to know about consuming alcohol.

They can consider your health and medications to help you make an informed decision and minimize potentially harmful effects.

How K Health Can Help

Did you know you can get affordable primary care with the K Health app? Download K to check your symptoms, explore conditions and treatments, and if needed text with a healthcare provider in minutes. K Health’s AI-powered app is HIPAA compliant and based on 20 years of clinical data.

Frequently Asked Questions

Can you drink liquor while taking metformin?
The metformin prescription instructions state that excessive (or binge) drinking and regular consumption of alcohol should be avoided. A few occasional drinks is usually fine unless you have other health conditions. Typically, wine or liquor mixed with water or seltzer are considered better choices than craft beers, sangria, or sweet cocktails. A healthcare provider can help you determine what is safe for you to consume.
How much alcohol can you drink while taking metformin?
If you take metformin and your diabetes is controlled, a few drinks infrequently will usually not cause a problem. However, consult your healthcare provider before drinking.
What does alcohol do to blood sugar?
Alcohol can lead to lower-than-normal glucose levels for up to 24 hours after consuming it. Most people who have diabetes can safely drink alcohol occasionally. Do not consume alcohol on an empty stomach or drink it when your blood glucose levels are already low. Also stay hydrated to minimize increased effects on your liver and kidneys.
K Health articles are all written and reviewed by MDs, PhDs, NPs, or PharmDs and are for informational purposes only. This information does not constitute and should not be relied on for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment.

K Health has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references.

Craig Sorkin, DNP, APN

Craig Sorkin, DNP, APN is a board certified Family Nurse Practitioner with over 15 years experience. He received his Undergraduate and Graduate degrees from William Paterson University and his doctoral degree from Drexel University. He has spent his career working in the Emergency Room and Primary Care. The last 6 years of his career have been dedicated to the field of digital medicine. He has created departments geared towards this specialized practice as well as written blogs and a book about the topic.