Your search for "effervescent tablet" revealed the following:

Sale price £34.26 Regular price £50.00 Sale
Sale price £46.87 Regular price £50.00 Sale
Sale price £79.99 Regular price £90.00 Sale
Sale price £39.42 Regular price £50.00 Sale
Sale price £37.99 Regular price £50.00 Sale
Sale price £46.10 Regular price £70.00 Sale
Sale price £85.53 Regular price £90.00 Sale
Sale price £163.22 Regular price £200.00 Sale
Sale price £69.92 Regular price £90.00 Sale
Sale price £12.99 Regular price £20.00 Sale