Why is not a good idea to drink alcohol while taking any medication

It is common to hear that we should not consume alcohol if we are taking any medication, but why?

Alcohol is metabolized (broken down) in the liver by important enzymes. Some drugs are also metabolized by the same or similar enzymes; depending on how often and how much alcohol is consumed, changes in how drugs are metabolized can occur in your body, empowering toxic effects of alcohol and/or drugs or decreasing its therapeutic effects.

The mechanism by which enzymes catalyze chemical reactions is similar to a lock and key, in fact, it is called “Lock and Key Theory”, the chemical reaction, in this case, metabolism, happens when the correctly sized key (substrate – drug or alcohol) fits into the key hole (active site) of the lock (enzyme). This explanation is to understand that when an acute amount of alcohol is consumed with any medication, the following cases may occur:

– Alcohol fits into enzyme: if it happens, the drug will still flow freely in the bloodstream because it was not fully metabolized by an enzyme, empowering toxic effects and side effects of the drug in the body.

– Drug fits into enzyme: if it happens, alcohol will flow freely through the bloodstream, improving its toxic effects.

These are the type of drugs you should be more careful with if you want to consume alcohol: anesthetics, antibiotics (mainly sulfamethoxazole/trimethoprim and metronidazole), antidepressants, antihistamines, antidiabetic medications, antipsychotic medications, antiseizure medications, antiulcer medications, cardiovascular medications (mainly nitroglycerin), narcotic pain relievers, non narcotic pain relievers, sedatives and hypnotics.

If you are not sure which type of medicine you are taking please do not hesitate to contact your physician, his advice can help you avoid the severe effects of an alcohol-drug interaction.

In general terms, you may need to wait at least 72 hours after finishing with your drug therapy before having any alcohol.