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Metformin and Alcohol: Can You Mix Them?

Updated on December 19, 2024
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What you need to know about drinking alcohol while taking metformin for type 2 diabetes management.

The diabetes drug Metformin (Glucophage) is one of the most commonly prescribed medications in the US. In fact, nearly 20 million Americans were taking metformin in 2021 alone. Metformin is approved for the treatment of type 2 diabetes. It’s also often prescribed off-label for weight loss in those with type 2 diabetes or prediabetes, and to treat insulin resistance related to PCOS.

If you’ve been prescribed metformin, you may be wondering if you can drink alcohol while taking this medication. This is a common question for people who are taking longer-term medications like metformin. After all, alcohol is widely available and advertised in the US. Whether you’re eating at a restaurant, out with friends or celebrating great news, drinking can be a big part of social culture.

In this blog post, we’ll explore how metformin and alcohol interact. We’ll also discuss if it's safe to mix them, and other risks and side effects of drinking as a type 2 diabetic.

How metformin works

Metformin works by helping the body control its blood sugar levels, also known as blood glucose levels.

This is important for those with type 2 diabetes because they have something called insulin resistance. Insulin is a hormone that controls blood glucose levels, and insulin resistance is when the body’s cells don’t respond well to insulin.

Insulin resistance is dangerous because it means that the body’s cells are ignoring the insulin’s signal to absorb blood sugar. Since the blood sugar isn’t getting absorbed, it builds up in the blood - and blood sugar levels rise. High blood sugar levels can be dangerous, causing health complications like nerve damage and blood vessel damage.

Metformin helps prevent this issue by stopping your liver from producing as much glucose. It also improves your body’s insulin sensitivity. In other words, it helps your cells to become more responsive to insulin so that they absorb blood sugar (glucose) more easily.

By decreasing glucose production and improving insulin sensitivity, metformin helps your body to maintain stable blood glucose levels. This, in turn, protects your body from long-term diabetes complications.

Side effects of metformin are generally mild. They include gastrointestinal issues like cramping, nausea, gas and indigestion.

Can I drink alcohol while taking metformin?

Generally, it’s ok to drink in moderate amounts while taking metformin. In other words, having a beer or a glass of wine every now and then shouldn’t be a problem if your diabetes is under control and if you don’t have health conditions that are worsened by alcohol, like kidney or liver issues.

For women, drinking in moderation looks like one drink per day. For men, it means no more than two drinks per day. One drink is defined as one 12-oz beer OR one 8-oz glass of malt liquor OR one 5-oz glass of wine OR one 1.5 oz of hard liquor such as vodka or whiskey.

However, it’s important to avoid heavy drinking (eight or more drinks per week for women and fifteen or more for men) or binge drinking (four or more drinks on a single occasion for women, and five or more for men) while taking metformin. Excessive alcohol use while using metformin can result in serious side effects, as detailed below.

Risks of excessive drinking on metformin

Excessive alcohol use while taking metformin can increase your risk of several serious side effects. This includes conditions like lactic acidosis (a build-up of lactic acid in the body) and hypoglycemia (low blood sugar). Both of these conditions can be life-threatening and require immediate medical attention.

Increased risk of lactic acidosis

While rare, lactic acidosis is one of the most serious risks of combining alcohol and metformin. Lactic acidosis occurs when there is a buildup of lactic acid in the body. Alcohol consumption can make this worse. This is because alcohol can increase the production of lactate while stopping the liver from clearing it from your blood.

Lactic acidosis can cause hypothermia, hypotension (high blood pressure) and other dangerous conditions. Symptoms of lactic acidosis include muscle pain, cramping, tiredness. You may also experience a feeling of cold, dizziness, a slow heart rate, or stomach discomfort. If you or a loved one experience any of these symptoms, seek emergency medical care.

Increased risk of hypoglycemia (low blood sugar)

Alcohol puts a lot of stress on your liver and can interfere with the liver’s ability to release glucose. This increases the risk of low blood sugar (hypoglycemia). Metformin slows down your liver’s ability to release glucose too, so alcohol and metformin can be a dangerous combination.

Symptoms of low blood sugar include shaking, sweating, fast heartbeat, dizziness, hunger, headache, and irritability. Like lactic acidosis, hypoglycemia can be a medical emergency and requires urgent treatment.

Additional side effects and interactions of metformin and alcohol

Lactic acidosis and hypoglycemia aren’t the only risks of mixing metformin with alcohol. Metformin also has side effects that can be exacerbated (worsened) by alcoholic drinks, including vitamin B12 deficiency and GI issues.

Vitamin B12 deficiency

Both metformin and alcohol can contribute to a decrease in vitamin B12 levels. Over time, this can lead to anemia and other health problems.

Gastrointestinal (GI) side effects

Alcohol can make certain GI side effects associated with metformin even worse. This includes nausea, vomiting, diarrhea, abdominal discomfort, and loss of appetite.

Some groups of people are also at higher risk of side effects from combining alcohol with metformin. Older adults, women and patients with kidney or liver issues are all more sensitive to the effects of alcohol.

Given these potential risks, it’s important to talk to your healthcare provider about your alcohol consumption. Make sure that you’re not drinking on an empty stomach in order to help stabilize blood sugar levels. Most importantly, know what moderate alcohol intake - and alcohol abuse - look like.

How Sesame can help

Moderate alcohol use may be safe for some people on metformin, but it also comes with significant risks. If you have type 2 diabetes and have questions about mixing alcohol while taking metformin, Sesame can help.

To get started, book a same-day virtual visit with an online diabetes doctor. Your provider can help you to identify what moderate alcohol use looks like. They can also assess your risk factors and ensure that you are safely managing your type 2 diabetes.