At some point in your life, you’ve most likely been prescribed an antibiotic –a medicine that works to inhibit the growth of or to destroy microorganisms.

On many antibiotic prescription bottle labels there’s an “Avoid Alcohol” warning, but with no further clarification, this label often times leaves people wondering, “Why?”

In most cases, small amounts of alcohol can be consumed while on an antibiotic; however, consuming excessive amounts of alcohol while on antibiotics could potentially lead to health risks like dehydration, and may hinder your body’s ability to naturally heal on its own.

Some antibiotics can also cause a variety of side effects when mixed with alcohol including dizziness, drowsiness and nausea.

However, it is important to know that there are certain antibiotics that create a more serious interaction when mixed with alcohol.

Perhaps the most common such interaction occurs with the antimicrobial agent metronidazole (Flagyl). This type of antibiotic is used for a number of infections that range from respiratory tract infections to skin, joint and gastrointestinal infections.

Mixing metronidazole with alcohol could potentially cause a reaction known as a “disulfiram-like reaction.” This reaction could cause flushing of the skin, headaches, breathlessness, stomach cramps, nausea, vomiting and rapid heart rate.

Other antibiotics can cause central nervous system side effects like confusion, dizziness, drowsiness or sedation when mixed with alcohol. This sort of reaction is due to the fact that alcohol is a central nervous system depressant. These reactions, while serious on their own, can be extremely dangerous if the patient is driving or operating heavy machinery.

Now, we are going to get a little more technical in order to better explain why mixing alcohol with antibiotics is not the best choice.

To begin, alcohol is broken down (metabolized) in the liver by an enzyme; this same enzyme also metabolizes some drugs. Depending on the amount and how often alcohol is consumed, this enzyme could in time affect how drugs are metabolized: When alcohol is consumed, the enzyme cannot metabolize the drugs as efficiently and effectively as it should. Therefore, the levels of the drug in the body could increase due to the fact that it’s not fully metabolized and excreted, thus leading to drug toxicity and side effects.

Though alcohol does not always reduce the actual effectiveness of most antibiotics, alcohol can decrease a person’s energy as well as delay the patient’s recovery time from a particular illness. That’s why it’s a good idea to avoid alcohol as much as possible until your antibiotic prescription is finished and you are feeling better.

As a note of reminder, in order for an antibiotic to work fully, you must finish all doses of the prescription. Even if you are starting to feel better, you must complete your medication regimen.

If you have additional questions about your medications and their interactions with alcohol, schedule a time to speak with your primary care physician.


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