From the FDA Drug Label
Alcoholic beverages should be avoided while taking metronidazole tablets and for at least one day afterward. Alcoholic beverages should not be consumed during metronidazole therapy and for at least one day afterward because abdominal cramps, nausea, vomiting, headaches, and flushing may occur Alcoholic beverages should be avoided when taking tinidazole and for 3 days afterwards
It is contraindicated to consume alcohol while taking antibiotics (such as metronidazole and tinidazole) because it may cause abdominal cramps, nausea, vomiting, headaches, and flushing.
- The exact mechanism is not explicitly stated in the label, but it is advised to avoid alcohol consumption during and after therapy to prevent these potential adverse effects.
- Patients should be counseled to avoid alcoholic beverages during and after treatment with these antibiotics 1 2.
From the Research
It is generally recommended to avoid consuming alcohol while taking antibiotics due to potential interactions that can lead to adverse effects, reduced efficacy of the medication, and increased risk of toxicity. The most recent and highest quality study on this topic, published in 2020 3, found that while some antibiotics can be safely used with concomitant alcohol consumption, others may have reduced efficacy or increased risk of toxicity. Some key points to consider include:
- Certain antibiotics, such as metronidazole and tinidazole, can cause severe reactions when combined with alcohol, including nausea, vomiting, headaches, flushing, and rapid heart rate.
- Other antibiotics, like cephalosporins, quinolones, and co-trimoxazole, may also interact with alcohol, though less severely.
- Alcohol can reduce the body's ability to fight infections and may worsen medication side effects like stomach upset, dizziness, and drowsiness.
- Alcohol can also stress the liver, which is responsible for metabolizing both the antibiotic and the alcohol. For best results, it is recommended to avoid alcohol completely during antibiotic treatment and for at least 48-72 hours after finishing the full course of antibiotics, especially with metronidazole or tinidazole, to ensure the body can effectively fight the infection and prevent potentially dangerous drug interactions. Additionally, studies have shown that alcohol and medication interactions can lead to adverse consequences, particularly in older adults 4 and individuals with mental health disorders 5. However, the evidence on alcohol and antibiotic interactions is often lacking and conflicting, highlighting the need for further research and caution when advising patients on alcohol consumption during antibiotic treatment 3, 6.