Your search for "effervescent tablet" revealed the following:

Sale price £24.49 Regular price £30.00 Sale
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Sale price £55.72 Regular price £70.00 Sale
Sale price £37.99 Regular price £50.00 Sale
Sale price £49.99 Regular price £70.00 Sale
Sale price £62.14 Regular price £90.00 Sale
Sale price £51.97 Regular price £70.00 Sale
Sale price £196.95 Regular price £250.00 Sale
Sale price £49.93 Regular price £70.00 Sale