How to choose
Look for the strain name on the label, not just 'probiotic' or 'lactic acid bacillus'. Lactobacillus rhamnosus GG (LGG) and Saccharomyces boulardii, a yeast, have the most studies for preventing diarrhoea during antibiotics. Bacillus clausii and Bacillus coagulans are spore-forming types common in India that survive stomach acid. Check the count (CFU or spores) and whether the pack needs refrigeration. Take bacterial probiotics about two hours apart from the antibiotic dose; Saccharomyces boulardii is not killed by antibiotics. Continue for a week after the antibiotic course ends. For children, choose drops or sachets made for their age and follow the dose on the pack. Probiotics do not cure an infection, and for constipation, bloating or IBS the evidence is mixed: try one product for four weeks, then stop if nothing changes.
Who really needs this
People on antibiotics who often get loose stools, children and adults recovering from a stomach upset, and travellers. Ask a doctor first, or avoid them, if you are very unwell, have a weak immune system or a central line, or for a premature baby. See a doctor for diarrhoea with blood, high fever, severe stomach pain, signs of dehydration (very little urine, a dry mouth, a drowsy child), or diarrhoea that is not settling after two days in a child or a week in an adult.
Our picks
Editorial recommendations, not paid placements.
For children
Vizylac GG Drops
Lactobacillus rhamnosus drops, measured by the dropper. Give alongside ORS, never instead of it.
With antibiotics, adults
An LGG or Saccharomyces boulardii capsule
The two types with the most evidence for preventing diarrhoea on antibiotics. Check the strain on the label.
Find it in the storeFor any loose motions
ORS, before anything else
Oral rehydration salts replace the water and salts lost in diarrhoea, which is what keeps children and older adults safe.
Find it in the store
Mistakes to avoid
Don't give a probiotic instead of ORS to a child with loose motions; dehydration is the danger. Don't take a bacterial probiotic at the same time as the antibiotic. Don't buy products that do not name their strains. Don't keep sachets or capsules that need cooling in a hot bag or car. Don't expect a probiotic to fix acidity, acne or weight. And don't take one for months without a reason; there is no proof that healthy people need one every day.
