CWeak evidence, or evidence againstOther
The short answer
A category, not a medicine. A product that does not name its exact strains is not evidence-based whatever the label says.
Who this is actually for
Some evidence for antibiotic-associated diarrhoea and for specific strains in irritable bowel syndrome. Benefits are strain-specific, not generic.
What it is legally allowed to claim
Nothing. There is no authorised EU health claim for this substance, so any packet promising a specific benefit is making a claim it is not entitled to make. That is worth knowing before you judge the price.
How much is too much
No upper level. Strain and dose matter more than count.
Cautions and interactions
Avoid in people who are severely immunocompromised, critically ill, or have central venous lines.
Ask a pharmacist before you start anything. Interactions with prescribed medicines are the most common way supplements cause harm, and they are easy to check. Bring the actual packet, or a photo of the ingredients panel, because doses and forms vary enormously between products. Nothing here is a substitute for advice about your own situation.