Your search for "effervescent tablet" revealed the following:

Sale price £149.98 Regular price £200.00 Sale
Sale price £87.34 Regular price £90.00 Sale
Sale price £19.99 Regular price £30.00 Sale
Sale price £66.99 Regular price £90.00 Sale
On Sale from £71.80 Regular price £90.00 Sale
Sale price £66.98 Regular price £90.00 Sale
Sale price £56.99 Regular price £70.00 Sale
On Sale from £36.99 Regular price £50.00 Sale