Pricing methodology

Prices shown on Chemist Prices are estimates and observations from published sources, not a quote from a specific seller - the amount charged at the counter can differ from the shown range.

How a price is built

Each price carries its own source and date. Where official NHS data exists - the Drug Tariff price or the Prescription Cost Analysis net ingredient cost per item (England only) - that figure is shown. Where it does not, we show a market price observed at a UK pharmacy or online chemist, labelled as an observation rather than a shelf price. Only as a last resort do we convert the published US NADAC price at the European Central Bank reference exchange rate; such derived estimates are always marked with ≈ and are reviewed as UK data becomes available.

Sources

Official prices come from the NHS Drug Tariff (NHSBSA) and the Prescription Cost Analysis dataset (NHSBSA open data, England only). Market observations come from UK pharmacy and online chemist listings, each stored with the page it was seen on and the date. Derived estimates use the published US NADAC dataset converted at the ECB reference rate. Supply-disruption notes follow the NHS Specialist Pharmacy Service (SPS, sps.nhs.uk). Every price on this site is labelled with its source and an "as of" date, and a price is never shown for a medicine or strength with no matching source record - we do not invent or interpolate a number.

Limitations

Drug Tariff and dispensing-cost figures describe the NHS position in England only, not a retail shelf price, and dispensing arrangements differ in Scotland, Wales and Northern Ireland. Market observations vary between sellers and over time. Derived estimates are approximations, always marked with ≈, and move with the exchange rate of the day. Nothing here is medical advice or an offer to sell any medicine.