Can I drink alcohol when I'm on antibiotics?

The treatment for STIs and other genital health issues is often a course of antibiotics.

When we send out chlamydia treatment to people who’ve tested positive for the infection, we’re often asked: can I drink alcohol while I’m taking these pills? So here’s the lowdown on drinking when you’re taking antibiotics to treat an STI.

On the whole, it’s best to stop drinking when you’re on a course of antibiotics. Or at least, limit how much you drink.

This is partly because with antibiotics, it’s really important to take the full course of tablets so that they work correctly. If you get drunk, you’re more likely to make a mistake with this. You might forget a dose, be sick or get diarrhoea, which can all affect how well the tablets work.

And even if you’re not drinking to the point of forgetfulness or throwing up, alcohol and antibiotics just aren’t a good mix.

For starters, doxycycline, the first line treatment for chlamydia, will not work as well if you drink while you take it. Azithromycin, another treatment for chlamydia, still works if you drink alcohol. But it can make you feel dizzy, so if you get that side effect it’s best not to drink as well.

Both these antibiotics have side effects that include an upset stomach and feeling sick, so it’s a bad idea to combine this with alcohol or anything that could make those feelings worse.

Metronidazole is another antibiotic that does not mix well with alcohol. It’s used to treat trichomoniasis and bacterial vaginosis. But if you drink when you’re taking it, it can cause very unpleasant side effects like nausea, vomiting, stomach pain, hot flushes, heart palpitations, headaches, feeling dizzy or drowsy. It's not anyone's idea of a good night out.

Once you stop taking metronidazole, you need to avoid alcohol for another 48 hours.

Whenever you’re prescribed medication, whether it's an injection in clinic or a course of tablets to take at home, always follow the advice and instructions that were given to you. Read the instructions that come with your medication carefully and in full before you start taking it. If you’re confused about anything, ask for clarification. Your clinician won’t mind, they want you to be safe and take your medication correctly.

And when taking antibiotics, it's important to take the course correctly and in full. If you miss any tablets or stop the course early, you might need further treatment.

Written by Helen Burkitt. Senior Sexual Health and Contraception Nurse
Published on: 15 February 2024