Your search for "effervescent tablet" revealed the following:

Sale price £64.90 Regular price £90.00 Sale
Sale price £33.90 Regular price £40.00 Sale
Sale price £77.99 Regular price £90.00 Sale
Sale price £41.76 Regular price £50.00 Sale
Sale price £33.45 Regular price £40.00 Sale
Sale price £26.99 Regular price £40.00 Sale
Sale price £17.99 Regular price £25.00 Sale
Sale price £32.82 Regular price £40.00 Sale
Sale price £33.45 Regular price £50.00 Sale
Sale price £56.89 Regular price £90.00 Sale
Sale price £29.90 Regular price £40.00 Sale