Antibiotics kill the bacteria causing an infection, but they also affect the “good” bacteria that live in your gut. That’s why up to 1 in 3 people get loose stools or diarrhoea during or after a course. Probiotics are often suggested to help. Here’s what they can and can’t do.
What are probiotics?
Probiotics are live “friendly” bacteria or yeasts, found in supplements like Lactic acid bacillus (Vizylac) and in foods such as yoghurt with live cultures, kefir and some fermented foods.
Do they help after antibiotics?
Research suggests some probiotics can reduce the chance of antibiotic-associated diarrhoea, especially in children. The evidence is strongest for certain strains, such as Lactobacillus rhamnosus GG and the yeast Saccharomyces boulardii. Results vary by strain and dose, so not every probiotic will work the same way.
How to take them with antibiotics
- Space them out. Take the probiotic at least 2 hours before or after your antibiotic dose, so the antibiotic doesn’t kill it.
- Start early. Begin on the first day of the antibiotic course.
- Keep going a little longer. Many people continue for 1–2 weeks after the antibiotics finish.
- Follow the pack. Doses and storage (some need the fridge) differ between products.
- Always finish your antibiotics as prescribed, even if you feel better.
Food that helps your gut recover
- Fibre-rich foods: oats, beans, lentils, fruit and vegetables feed your good bacteria.
- Fermented foods: live yoghurt, kefir, sauerkraut and kimchi.
- Plenty of fluids, especially if you have loose stools.
Who should check with a doctor first
- People with a weakened immune system, for example during chemotherapy or after a transplant
- People who are seriously ill, or have a central line or catheter
- Premature babies
- Anyone pregnant or breastfeeding
When diarrhoea needs a doctor
See a doctor straight away if you have severe or watery diarrhoea many times a day, blood in your stool, a fever, or bad stomach cramps during or after antibiotics. These can be signs of a C. difficile infection, which needs treatment. Read more in our guide to stopping diarrhoea.
This article is for general information only and isn’t a substitute for advice from a doctor or pharmacist. Always read the label before using any medicine.