All guides

Prescription food and online pharmacies

How to get prescription diets and medicines legally online — and what to ask your vet first.

Updated 15 July 2026

Prescription diets and long-term medicines can be expensive when bought directly from a practice. UK law allows you to buy them elsewhere, provided you have a valid prescription.

Getting a prescription from your vet

  • Vets must provide a prescription if you ask for one. They can charge a reasonable fee for writing it.
  • Prescriptions for medicines are usually valid for six months; some controlled drugs have stricter limits.
  • Prescription food does not always need a written prescription, but some retailers require one to confirm suitability.

What to check with an online pharmacy

  • Look for the Veterinary Medicines Directorate (VMD) accreditation symbol or registration as a UK pharmacy.
  • Check expiry dates, storage conditions and delivery times — refrigerated items need special handling.
  • Be wary of unusually cheap products from unknown sellers; counterfeit pet medicines do exist.

When the practice price is worth it

Buying from your vet can be simpler for urgent medication, and some practices will price-match reputable online pharmacies. It is worth asking before assuming online is always cheaper.

Affiliate disclosure

Some retailer links on this page may earn Compare-Vets a commission. We only include pharmacies and food retailers that meet UK regulatory standards.

More guides