Your search for "effervescent tablet" revealed the following:

Sale price £38.99 Regular price £50.00 Sale
On Sale from £68.33 Regular price £90.00 Sale
Sale price £39.19 Regular price £50.00 Sale
On Sale from £69.99 Regular price £90.00 Sale
Sale price £278.90 Regular price £300.00 Sale
Sale price £88.51 Regular price £130.00 Sale
On Sale from £59.86 Regular price £90.00 Sale
Sale price £39.95 Regular price £50.00 Sale
Sale price £129.05 Regular price £150.00 Sale
Sale price £50.85 Regular price £70.00 Sale
On Sale from £24.70 Regular price £30.00 Sale
Sale price £78.99 Regular price £110.00 Sale