Deceptive healthcare ads aren’t allowed in Europe either. Consumer protection standards are much higher.
You're not allowed to advertise it to the general public. You can still advertise it to prescribers and suppliers.
https://www.gov.uk/guidance/advertise-your-medicines
> You can’t advertise prescription-only medicines (POMs) to the general public but you can promote them to healthcare professionals and others who can prescribe or supply the product.
"Probiotic" term has been banned on ads and packages. Those products are now sold as "Ultrabiotic" or other variants. Same product, same impact on consumer, but legal.