Alcohol can interact with certain antibiotics, including Flagyl (metronidazole). Flagyl is a commonly prescribed antibiotic that treats parasitic and bacterial infections, including those in the abdomen, skin, and vagina. Although some antibiotics are relatively safe to use while drinking a moderate amount of alcohol, Flagyl is not. Mixing alcohol and Flagyl can cause and exacerbate side effects of each substance.
Flagyl is commonly used to address symptoms associated with the following:
- Abdominal infections
- Skin infections
- Bone and joint infections
- Central nervous system infections
- Respiratory infections
- Infections of the heart’s lining
- Other bacterial infections
The drug is available as a pill as well as a cream, gel, or lotion for rosacea treatment. Also, Flagyl-based vaginal gel can be used to treat bacterial vaginosis in women who are not pregnant.
Side Effects of Mixing Alcohol and Flagyl
The body relies on specific enzymes to metabolize alcohol into byproducts to be cleared from the body. Several byproducts are produced through this complicated process, one of which is a toxic substance called acetaldehyde. Flagyl can impair the functioning of enzymes responsible for breaking down acetaldehyde.
When this interaction happens, acetaldehyde can accumulate up in the body and is one of the primary causes of alcohol’s adverse effects, including the following:
- Stomach cramps
- Nausea and vomiting
- Shortness of breath
The second step in the breakdown process is when the body reduces acetaldehyde to acetate using an aldehyde dehydrogenase enzyme. Flagyl blocks the effects of this enzyme. As a result, an individual taking Flagyl cannot fully digest alcohol, and drinking can cause acetaldehyde to accumulate in the bloodstream.
For this reason, persons who drink alcohol while using Flagyl may experience a reaction similar to disulfiram, a prescription medication that can help treat alcohol addiction. Combining disulfiram and alcohol can result in health effects that discourage individuals from drinking.
A disulfiram-like reaction can occur when alcohol interacts similarly with a drug other than disulfiram, such as Flagyl. When an individual mixes Flagyl and alcohol, their response may be mild-moderate and include the following:
- Nausea and vomiting
- Rapid heartbeat
- Low blood pressure
- Facial flushing
- Stomach pain
- Hot flashes
Authors of a 1996 study report the death of a 31-year-old female who drank alcohol while using metronidazole.
Reactions will not occur in everyone. This may suggest that the risk of experiencing a disulfiram-like reaction to Flagyl and alcohol varies between individuals. But because doctors cannot determine a person’s risk of this reaction, everyone should avoid drinking alcohol while taking Flagyl.
The manufacturers of metronidazole-based creams, gels, and lotions cannot rule out the possibility of disulfiram-like reactions. Doctors and pharmacists should remind people who are using topical metronidazole products to avoid alcohol.
Taking Flagyl and consuming alcohol can have similar effects, which may be more pronounced when an individual uses the two in conjunction. Alcohol use can cause the stomach- and digestion-related side effects of Flagyl to be more severe.
While some individuals do not experience potentially adverse effects of mixing alcohol and Flagyl, health providers and pharmacists recommend avoiding alcohol as a safety precaution. This can reduce the likelihood of Flagyl causing side effects.
Alcohol may also impair a person’s seizure threshold. Since Flagyl can cause seizures, individuals with a history of seizures should be cautious and avoid alcohol consumption while taking the antibiotic. These effects typically occur 5-15 minutes after drinking alcohol.
Flagyl can increase an individual’s sensitivity to alcohol. Even having a minimal amount of alcohol while taking Flagyl can make some people very ill. They experience nausea and vomiting, and potentially shortness of breath.
How Long Flagyl Remains in Your System
After your last dose of Flagyl, the drug can remain in a person’s system for some time. It may be cleared from a person’s body within two days or 48 hours, but the elimination rate varies depending on the individual’s age and metabolic rate, among other factors.
The maker of Flagyl, Phizer, recommends waiting at least 24 hours after the last dose of Flagyl before drinking alcohol. However, some experts recommending waiting as long as three days after the last dose.
Another factor that may influence how long Flagyl remains in a person’s system is liver functioning. The liver eliminates metronidazole from the body, so if you have impaired liver function because of alcoholism or another reason, you should let your health provider know.
As noted, drinking alcohol while using Flagyl can cause serious side effects. Physicians and pharmacists advise individuals to avoid alcohol entirely while using the medication in any form, including oral tablets and topical creams.
So When Is it Safe to Consume Alcohol Again?
The unwanted interactions between alcohol and Flagyl, specifically Flagyl’s inhibition of aldehyde dehydrogenase, may continue for up to three days after an individual stops using the antibiotic. As a result, health providers and pharmacists generally recommend avoiding alcohol while taking Flagyl and for several days after the last dose due to the risk of side effects.
For those applying metronidazole products to their skin or using vaginal gel, drug makers recommend avoiding alcohol consumption until 24 hours after the last application.
Using Flagyl safely
As noted, a person should not consume alcohol until at least three days after the last dose of Flagyl.
Flagyl can accumulate in the bloodstream of an individual with impaired liver function, and health providers often prescribe lower dosages to those with severe liver disease. Persons with renal failure have a similar risk, and physicians should watch carefully for signs of accumulation.
The medication can also accumulate more rapidly in older individuals above age 70 who have no liver or kidney failure signs. Health providers may prescribe the regular dosage to geriatric adults but monitor them closely for side effects. Physicians and pharmacists should also advise everyone taking Flagyl to avoid alcohol while using the drug and for three days following the final dose.
Persons applying antibiotics to their skin should avoid alcohol throughout treatment and 24 hours after the last application.
Getting Treatment for Addiction
If you or a loved one needs treatment for an alcohol use disorder, please don’t hesitate to seek professional help. Just Believe Detox and Just Believe Recovery offer specialized alcohol and drug addiction treatment programs that include therapeutic modalities and activities, such as the following:
- Individual/family counseling
- 12-step group support
- Relapse prevention
- Health/wellness education
- Substance abuse education
- Meditation and yoga
- Art and music therapy
- Aftercare planning
- Alumni programs
We are dedicated to ensuring each and every person we treat receives the most effective, state-of-the-art care available and the education, tools, and support they so direly need to sustain long-term happiness and well-being.