Weight-loss medication is not bought once. It is escalated through strengths over months, and every strength has its own price at every pharmacy. Comparing the starting dose — the number most providers advertise — tells you about one month of a treatment that typically runs for many.
When we priced a full escalation across UK pharmacies using live data, the difference between choosing on starting price and choosing on total course cost came to hundreds of pounds over six months. Same medicine, same doses, same duration.
Why the Gap Opens Up
UK pharmacies price these medicines in two broadly different ways.
Flat-rate pricing
Some providers charge the same monthly amount whatever strength you are on. At the starting dose they look expensive. By the time you are at a higher dose they can be the cheapest option available.
Per-strength pricing
Others price each strength separately, rising as the dose climbs. These providers dominate the "cheapest starter price" listings and can become significantly more expensive later.
Neither model is dishonest. But a comparison that only shows the starting dose systematically favours the second model, regardless of what a patient will actually pay.
What a Course Actually Looks Like
Escalation schedules are set by the licensed dosing for each medicine — typically a step up every four weeks, with time held at each level. That means a predictable sequence of strengths, and therefore a predictable sequence of prices, if you know what each provider charges at each one.
Two caveats keep this honest:
- Not everyone escalates to the top. Some people stay at a middle dose because it works or because side effects make higher doses unpleasant.
- Not every pharmacy stocks every strength. A provider that prices only part of the ladder cannot be compared on a full course — and if you include them anyway, they will appear cheapest precisely because they are missing the expensive steps.
How to Compare Properly
- Ask for the price at every strength, not the starting one. A provider unwilling to publish that is telling you something.
- Work out your likely path. Even a rough plan — how many months at each dose — turns a list of prices into a total.
- Check whether the price includes the consultation, the prescription and delivery, or whether those are added later.
- Check stock at the higher strengths. A cheap price for a dose that is never in stock is not a price.
- Re-check before each step up. Prices in this market move, and the provider that was right for month one may not be right for month five.
Switching Mid-Course
You are not locked in. Moving to a different pharmacy at a dose change is straightforward in principle — you need a new prescription and continuity of supply, so plan it so you do not run out mid-switch.
What you should not do is switch on price alone if the cheaper provider cannot supply reliably. A gap in treatment means dropping back down the escalation, which costs both time and money.
The Underlying Point
A single price is a snapshot of one month of a months-long commitment. The number that matters is what the whole course costs at the doses you will actually take — which is the comparison this site is built to make.