A few antibiotics should not be mixed with any amount of alcohol. These include metronidazole (Flagyl), tinidazole (Tindamax) and sulfamethoxazole-trimethoprim (Bactrim, Septra). Many patients get prescribed this common antibiotic without realizing that mixing it with alcohol might cause unpleasant side effects. When alcohol and metronidazole mix in your system, you might experience nausea, vomiting, stomach pain, hot flushes, headaches, and even heart palpitations. It is best to avoid alcohol while taking metronidazole. Alcohol can cause reactions in addition to the regular side effects of this drug. Some of these reactions can be severe. Drinking alcohol while taking Flagyl (metronidazole) can trigger a cluster of unpleasant symptoms: flushing, nausea, vomiting, rapid heartbeat, and a drop in blood pressure. Symptoms may include flushing, headaches, nausea, vomiting, and stomach cramps. There has been one reported death associated with this reaction. The product information and health professionals recommend not to drink alcohol during metronidazole treatment and for 3 days after finishing the course. The FDA-approved drug labeling for metronidazole clearly states: Alcoholic beverages should not be consumed during metronidazole therapy and for at least one day afterward. Medical guidance recommends waiting a minimum of 48 hours following the final dose of metronidazole before consuming any alcohol. This two-day waiting period provides a margin of safety, allowing the active drug to be substantially eliminated from the body. Despite the widespread belief that metronidazole is contraindicated with alcohol consumption, the literature raises doubt. Interaction occurs with unclear frequency, and, when it occurs, it ensues with varying severity. It can occur when alcohol is consumed with certain antibiotics, such as metronidazole, tinidazole and certain cephalosporins. Metronidazole (Flagyl) is the antibiotic most commonly associated with this interaction. Key takeaways: You shouldn’t mix metronidazole (Flagyl) and alcohol. The mixture could lead to nausea or vomiting, fast heart beat, and flushing of the face. You should avoid alcohol while taking metronidazole and for at least 3 days after your last dose.