Antibiotics and alcohol: What you need to know

Health professionals generally recommend avoiding alcohol when you’re unwell.

If you do plan to drink alcohol while taking antibiotics, it’s important to understand how the 2 interact and to know the risks.

The information provided here is a general guide only. It’s always best to discuss the side effects of any medication with your GP or pharmacist.

The liver breaks down any medications we take, including antibiotics.

Drinking alcohol can interfere with this process, as the liver also processes alcohol.¹

Combining the 2 can put strain on this vital organ, leading to an increased risk of side effects and the chance of medication toxicity, says Bupa GP Samantha Saling.

“Think about it this way,” says Samantha. “The liver is the engine room of our body’s metabolic needs. It's working hard all day, every day to break down what we eat, what we drink, and waste products from our cells. So, if we add in alcohol, this makes the liver work even harder, therefore reducing its capacity to deal with other substances like medications.”

It has been widely reported that certain antibiotics, specifically metronidazole (brand names include Acea, Anabact, Flagyl, Metrogel, Metrosa, Rosiced, Rozex, Vaginyl, Zidoval and Zyomet), can cause a severe reaction in the body.

This is known to medics as a DLR (disulfiram-like reaction) and is considered to be due to a buildup of acetaldehyde in the blood, causing nausea, vomiting and flushing.

Modern research, however, has questioned the validity of this claim, suggesting its frequency and severity might be lower than once thought. That’s not to say that drinking alcohol with your antibiotics is a good idea, however.

“In general, taking any antibiotic with alcohol is a no-go,” says Samantha.

Drinking a small amount of alcohol will not generally lower the effectiveness of most antibiotics², but it may not be the best combination.

Some antibiotics can have side effects that might be made worse by drinking alcohol.

“Alcohol can worsen side effects of antibiotics, such as dizziness, nausea, headaches and abdominal pain,” says Samantha. “But it really depends on the mix of medication and alcohol. Always check the risks of particular medications with your GP.”

Alcohol can also weaken your immune system, making it harder for your body to fight the infection you’re taking the antibiotics for.

Avoiding alcoholic beverages while you are sick is usually a good idea. It may cause dehydration and interrupt your sleep patterns, which is the last thing you want when you’re feeling crook to begin with.

“Alcohol is classified as a depressant,” explains Samantha. “Depressant drugs tend to slow down messages between the brain and the rest of the body. This can affect recovery from any illness.

“There’s usually a good reason someone is prescribed antibiotics, so I wouldn’t recommend combining alcohol at the same time. It's best to focus on completing one’s prescribed treatment and reducing any external stressors on the body during this time.”

Note: it's recommended that you wait at least 48 hours after completing a course of antibiotics before you introduce alcohol into the equation.

The Alcohol and Drug Foundation provides comprehensive information on how alcohol interacts with various prescription medications, including antibiotics.

If you're concerned about your own or someone else's alcohol and other drug use, call Alcohol and Drug Information and Support Services (ADIS) 24/7 on 1800 177 833.