Alcohol and Antibiotics – Is it safe?

Is it safe to mix antibiotics and alcohol?

It is widely believed that consuming alcohol with antibiotics is not safe. In general, drinking any amount of alcohol when you are sick may not be a good idea, as alcohol consumption can lead to dehydration, disturb your normal sleep cycle, and may also hinder your body’s natural ability to heal itself. Besides these, some antibiotics have sometimes very dangerous interaction with alcohol. Commonly you might have seen the avoid alcohol warning labels on medicines. So, it is obvious why people are worried about mixing alcohol or products containing alcohol with antibiotics. But the question here is do you need to avoid alcohol while you are on antibiotics?

What are antibiotics?

Antibiotics are drugs that kill bacteria or stop them from reproducing in your body to treat infections. They are very commonly prescribed and are important classes of drugs for treating a variety of infections. Most of the times the side effects of antibiotics are not life harming. However, antibiotics can cause severe side effects.

The Centers for Disease Control and Prevention (CDC) estimates that severe side effects of antibiotics are responsible for 1 in 5 medicine-related emergency doctor visits. Some of the common side effects of antibiotics are –

  • Nausea
  • Diarrhea
  • Indigestion and bloating
  • Pain in abdomen
  • Loss of appetite

You may also have other severe side effects including

  • Fungal infections
  • Drug interactions
  • Photosensitivity
  • Staining of teeth and bone
  • Anaphylaxis
  • Colitis
  • Antibiotic resistance
  • Kidney failure

Apart from all these side effects of antibiotics, if you consume alcohol with antibiotics, it would be a dangerous mix.

Not all antibiotics have severe interactions with alcohol. Usually your doctor may give recommendations on your alcohol intake depending on the type of antibiotic you are on. They recommend not taking alcohol with a number of drugs. The biggest concern is that when you consume alcohol with antibiotics, it can increase your risk of side effects.

What happens when you mix alcohol with antibiotics?

Alcohol doesn’t make antibiotics less effective, but it could raise your risks of dangerous side effects. It makes antibiotics less effective at removing bacteria. The combination of alcohol and antibiotics can cause unpleasant side effects.

In certain cases, the levels of a drug in your blood might get changed with the consumption of alcohol which could change its effectiveness.

Alcohol is broken down in the liver by the enzymes. Some drugs are also metabolized by the same enzymes. Changes in the enzymes may change how drugs are broken down in your body, it all depends on how often and how much alcohol you have consumed. When you consume an acute amount of alcohol over a short period of time, some enzymes are inhibited i.e. the drug cannot be broken down as effectively as normal. So, as antibiotics are not fully metabolized and excreted, the levels of antibiotics in your body increases and could lead to drug toxicity and you may experience the unpleasant side effects.

Alternatively, when alcohol is abused constantly on a daily basis, levels of enzymes may become induced i.e. the drug is being broken down at a more efficient rate and the levels of drug may decrease in your body.

When the levels of antibiotic decrease in your bloodstream, your infection may not be treated, and in turn antibiotic resistance may occur. With lowered drug levels in your body, the desired effect of antibiotics may not be achieved in your body.

Ask your doctor if your antibiotic interacts with any liver enzymes, and if you have any concerns about the effectiveness of the drug for your infection based on the interactions.

Do not consume alcohol with the following antibiotics 
  • cefoperazone
  • cefotetan
  • doxycycline
  • erythromycin
  • metronidazole
  • tinidazole
  • ketoconazole
  • isoniazid
  • linezolid
  • griseofulvin

When your body breaks down alcohol, it produces acetaldehyde that can cause nausea. Many people also experience side effects of stomach when taking antibiotics. Drinking alcohol with antibiotics may increase nausea due to side effects. Although most of the people experience nausea while taking alcohol with antibiotics, not everyone experiences this side effect when combining both.

Although modest use of alcohol use doesn’t make alcohol less effective, it can reduce your energy levels and delay your recovery from illness. So, it’s good to avoid alcohol until the end of your antibiotic treatment and you start feeling better.

According to a study published in Progress in Neuro-Psychopharmacology and Biological Psychiatry, moderate alcohol consumption is associated with a lower risk of infection. The study also states that moderate alcohol consumption is associated with reduced inflammation and improved responses to vaccination, while chronic heavy drinking is associated with a decreased frequency of lymphocytes and increased risk of both bacterial and viral infections. However, it says that due to lack of systematic studies examining the effect of multiple doses and different time courses, the mechanisms by which alcohol exerts a dose-dependent effect on the immune system remains poorly understood.

The Centers for Disease Control and Protection (CDC) defines a moderate alcohol consumption as

  • a drink per day for women
  • two drinks per day for men

The CDC also defines binge drinking as consumption of four drinks for women and five for men at a single time. It defines heavy drinking as eight or more drinks for women and 15 drinks or more for men per week.

Researchers have linked binge and heavy drinking with an impaired immune system. People with a weakened immune system have a higher risk of infection.

Consuming alcohol with the following drugs can be dangerous 

The class of tetracycline antibiotics includes doxycycline and minocycline. This class can treat a wide variety of bacterial infections. You should not drink alcohol while taking doxycycline as it may reduce the effects of the medicine.

Alcohol speeds up the elimination of doxycycline from the body and therefore makes it less effective.

Rare side effect of taking minocycline is liver toxicity. You should avoid consuming alcohol while taking minocycline as alcohol also has side effects on the liver.


Linezolid comes under the oxazolidinone class of antibiotics. Doctors prescribe oxazolidinones for treating skin, abdominal, lung, and urinary tract infections.

Linezolid has antibacterial effect. It reduces the action of enzymes called monoamine oxidase-A and monoamine oxidase-B. Monoamine oxidases break down tyramine which is a substance that is present in tap beers and red wine.

When you consume tap beer and red wine along with linezolid, tyramine amount in your blood rises. You may experience mild, moderate or even serious side effects after taking alcohol while taking oxazolidinone class of antibiotics.

Side effects of taking alcohol while taking this class of antibiotics.

  • Agitation
  • Rapid heartbeat
  • Unusual sweating
  • Fever
  • Changed mental status
  • Rapid breathing
  • Vomiting
  • Abnormal heart rate
  • High blood pressure
  • Seizures
  • Coma
  • Muscle rigidity
  • Muscle spasms

You should avoid tap beers and red wine with this class of antibiotics. Cheeses and smoke meats should also be avoided as these products also contain tyramine.


Doctors prescribe sulfonamide antibiotics for treating urinary, respiratory, and abdominal infections. Sulfonamide class of antibiotics includes combination drugs sulfamethoxazole and trimethoprim. These drugs are also called Septra.

The folic acid in bacteria is affected by sulfamethoxazole and trimethoprim. In rare cases, trimethoprim can also affect the metabolism of folic acid in humans. Those who are deficient in folic acid may be at risk of reducing the folic acid levels in their body while taking sulfamethoxazole and trimethoprim.

Those who drink alcohol regularly may also have lower levels of folic acid in their body and therefore they should be careful while using sulfamethoxazole and trimethoprim. Doctors should also be careful while prescribing sulfamethoxazole and trimethoprim to people who drink alcohol often, though, an drinking occasionally with sulfonamides is safe.


The Food and Drug Administration (FDA) in 2018 published updates safety measures for all flooroquinolone antibiotics. The labels of these antibiotics now mention the mental side effects including

  • Attention disturbances
  • disorientation
  • agitation
  • nervousness
  • memory loss
  • confusion

When you mix alcohol with fluoroquinolone antibiotics, it may increase the mental health side effects.

In rare cases, people may experience seizures with fluoroquinolone. People with a history of seizures are more likely at risk. Doctors usually advise people with a history of seizures to avoid taking alcohol with fluoroquinolones as alcohol lowers the threshold of seizures.

Drinking occasionally with fluoroquinolone can be safe, but regular drinking may cause side effects of central nervous system.


Metronidazole comes under the class of nitroimidazole antibiotic. These antibiotics are prescribed by doctors for treating sexually transmitted infections, abdominal infections, and other anaerobic bacterial infections.

Metronidazole affects the functioning of an important enzyme called aldehyde dehydrogenase that helps the body to digest alcohol. When metronidazole inhibits this enzyme, it causes the levels of this enzyme to accumulate in your blood. This causes the side effects of alcohol.

Mixing alcohol with metronidazole may cause:

  • abdominal cramping
  • nausea
  • vomiting
  • headaches
  • facial flushing

You should avoid drinking alcohol during metronidazole treatment. Even up to 3 days after the last dose, you should not consume alcohol.

Not everyone will experience these reactions when drinking while taking metronidazole. Still, you should refrain from consuming alcohol while taking metronidazole.

General side effects of antibiotics

The side effects that an antibiotic can cause depend on the type of medicine you are taking. However, some common side effects of antibiotics include
  • nausea
  • sleepiness
  • dizziness
  • lightheadedness
  • diarrhea
Alcohol can also cause side effects including
  • an upset stomach
  • digestive problems like ulcers, stomach pain, and diarrhea
  • tiredness
Warning signs of an alcohol-antibiotic reaction include
  • flushing
  • severe headache
  • rapid heart rate

Most of the times, the side effects get resolved on their own. If you think you’re having a severe reaction, call your doctor immediately.

Getting plenty of rest, drinking lot of fluids, eating a nutritious diet and taking your medication on time is what helps when you are sick. Avoiding alcoholic beverages during sickness is usually a good idea to avoid any kind of complications and also to make the healing happen quickly.

Consuming alcohol can disrupt your sleep patterns and can stop you from getting a good night’s sleep. It can stop your body from absorbing all the essential nutrients. It can also raise your blood sugar levels and decrease your energy levels.

All these factors will make you lower your body’s ability to heal from an infection. Alcohol consumption in any form, whether it is binge drinking, acute alcohol consumption or chronic alcohol use, is always harmful whether or not you are on medication.

Alcohol isn’t limited to beer, wine, liquor, and mixed drinks. Many over-the-counter medicines also contain alcohol in the formulation including
  • Cough medicines
  • Cold or flu medicines or products
  • Mouthwashes

So, make sure to read the ingredient labels on products and medications to check whether they contain alcohol or ethanol. Either check the packaging of the medicine or ask your doctor about it. Prescription medicines also contain alcohol. You should always check with your doctor each time you receive a new prescription to see if there are any important drug interactions. Also, if you have had any antibiotic-alcohol reaction in the past, make sure to talk about it to your doctor. Ask your doctor if it is safe to use these products while being on antibiotics.


If your doctor tells you to refrain from alcohol consumption, ask how long you should wait before drinking again. You may need to wait for at least 3 days until your last date of antibiotics treatment before having any alcohol. Doctors usually prescribe antibiotics only for a short duration of time. You need to be on antibiotics only for a week or two to recover from an infection.

Following your doctor’s advice can help you avoid the effects of an alcohol-drug interaction.



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