I don't know anything about mail order companies in the UK, but here in the US there are several reputable mail order pharmacies that carry pet medications. The are always less expensive than what you will pay to a vet, both because mail order has a lot lower overhead and because vets make a significant income from marking up the cost of meds. However, some of the US companies may not do international shipping and of course international shipping can be pretty expensive.
thanks for advice she has been the best cat ever Lap cat hot water bottle and comfort blanket when needed, so maybe she should get the expensive pills. mind she will only take them hidden in tiger prawns, she's no cheap date I tell ya.
IMO any medications bought online would be dodgy.....search the site and ask your Vet for his opinion if its a reputable site first....a few dollars saved isn't worth risking NoNo's health.