Dulaglutide and semaglutide: understanding the difference for weight management

The licensing gap, and why it affects your options

Many people arrive at this comparison having heard that both medicines work similarly, and that is partly true at a mechanistic level. Both activate the GLP-1 receptor, reducing appetite and slowing the rate at which the stomach passes food into the small intestine. The misconception worth letting go gently is that this shared mechanism makes them interchangeable for weight loss. It does not.

Dulaglutide (Trulicity, made by Eli Lilly) is licensed in the UK for glycaemic control in adults with type 2 diabetes. Its dose range runs from 0.75 mg to 4.5 mg per week, and its clinical programme was built around blood-sugar targets, not the sustained weight reductions that are now central to modern obesity medicine. Semaglutide, by contrast, was put through a separate, higher-dose clinical programme specifically for weight management. The NHS medicines page for semaglutide covers this distinction clearly, and the NHS medicines guidance on weight-loss injections explains what licensed options are currently available to UK patients.

Prescribing dulaglutide for weight loss in the UK would be an off-label use. That does not make it impossible (prescribers sometimes prescribe off-label when the evidence supports it) but it sits outside the licensed indication, carries different accountability, and is not what you will be offered through a regulated weight management service. If you are wondering whether dulaglutide and semaglutide are really the same medicine, the differences in licensing and clinical application make a compelling case that they are not. For the purpose of this comparison, the practical route to semaglutide or related medicines for weight loss is through a licensed product prescribed after proper assessment.

What the evidence says when semaglutide and dulaglutide are put side by side

The clearest direct comparison comes from the SUSTAIN 7 trial, which compared semaglutide 0.5 mg and 1.0 mg against dulaglutide 0.75 mg and 1.5 mg respectively in adults with type 2 diabetes. At both dose levels, semaglutide produced meaningfully greater reductions in body weight alongside better glycaemic outcomes. This was within the diabetes indication, not the weight-management programme, but it shaped clinical thinking about the relative potency of each medicine.

The weight-management data for semaglutide comes from a dedicated trial programme at higher doses than those used in diabetes. STEP 1, published in the New England Journal of Medicine, reported an average body-weight reduction of around 15% over 68 weeks with semaglutide 2.4 mg in adults with obesity or overweight and at least one weight-related condition, without diabetes. No equivalent high-dose weight-management trial exists for dulaglutide, because its manufacturer did not pursue that indication.

There is also now an oral form: the Wegovy tablet, approved by the MHRA on 11 June 2026, reached an average weight loss of around 13.6% over 64 weeks in its pivotal trial, rising to about 17% among participants who stayed fully adherent to treatment. Dulaglutide has no approved oral counterpart for weight management. If the injection format concerns you, that option is worth discussing when you explore weight management treatment options.

Who semaglutide is licensed for, and how that compares to dulaglutide's indication

The Wegovy injection is licensed in the UK for adults with a BMI of 30 or above, or a BMI of 27 to 29.9 alongside at least one weight-related condition such as high blood pressure, raised cholesterol, type 2 diabetes or obstructive sleep apnoea. Lower BMI thresholds can apply for certain ethnic backgrounds under UK clinical guidance. The Wegovy tablet carries the same criteria. NICE's appraisal of semaglutide (TA875) recommends it within specialist weight management services, and the full eligibility picture (including NHS versus private routes) is covered in the Wegovy overview.

Dulaglutide's licensed population is adults with type 2 diabetes, full stop. Weight reduction may occur as a benefit alongside glucose control, but patients are not prescribed it for that reason through any licensed pathway.

The decision between semaglutide and dulaglutide for weight loss is, in practice, already made by the regulatory framework: semaglutide is the licensed option. What remains a clinical decision is which formulation suits you, at what starting dose, and whether your health history makes any GLP-1 medicine appropriate at all. A prescriber at a regulated clinic reviews all of that individually.

Cost context and what to factor in when comparing options

Since Eli Lilly revised UK list prices in September 2025, private Wegovy pricing has settled at roughly £149 to £375 per month depending on dose and provider, based on widely reported market data. Dulaglutide for diabetes is available on NHS prescription where clinically indicated, which makes a direct private cost comparison less meaningful for most people.

For those pursuing semaglutide privately for weight management, the UK Wegovy price comparison page sets out what to look for and what headline prices sometimes omit, consultation fees, aftercare, prescription costs and delivery. A full-service private clinic bundles all of those into one figure; knowing that in advance prevents surprises. Whatever route you explore, a prescription from a GPhC-registered pharmacy is the only legally compliant way to obtain semaglutide for weight management in the UK. Suspect sellers offering GLP-1 medicines without a clinical assessment are flagged by the MHRA as a serious safety risk, and the MHRA Yellow Card scheme accepts reports of suspect products.

If you are ready to talk through whether semaglutide is right for your situation, you can start your free consultation with our prescribers and receive a same-day clinical review.