Who can use weight loss treatment

Prescription weight loss medicine is for people whose weight is affecting their health, not for cosmetic slimming. Here is exactly how prescribers decide.

Clinician in a white coat outdoors

The BMI rules

For most adults, treatment is licensed for:

  • BMI of 30 or above, or
  • BMI of 27 or above with at least one weight-related condition, such as high blood pressure, prediabetes, type 2 diabetes, high cholesterol, sleep apnoea or fatty liver disease.

These thresholds come from the medicines' licences, and private prescribers follow them just as the NHS does.

Lower thresholds for some backgrounds

Health risks from weight arrive earlier for people of South Asian, Chinese, Black African and African-Caribbean backgrounds, so prescriber guidance applies thresholds about 2.5 BMI points lower. Tell us your background in the health check and we apply the right threshold.

Age limits

We treat adults aged 18 to 75. Under 18s need specialist paediatric services through the NHS. Over 75, the balance of benefit and risk needs a GP or specialist who knows your full history, so we refer on rather than prescribe remotely.

Conditions that rule treatment out

A prescriber will decline treatment if you have:

  • Pregnancy, breastfeeding, or plans to conceive within the next 2 months
  • A history of pancreatitis
  • Personal or family history of medullary thyroid carcinoma, or MEN2 (multiple endocrine neoplasia type 2)
  • Type 1 diabetes
  • A current or recent eating disorder, such as anorexia or bulimia
  • Severe gastrointestinal disease, such as gastroparesis

Some conditions do not rule treatment out but change the plan: past gallstones, kidney disease, diabetic retinopathy and thyroid tablets all need a conversation.

Medicines that need care

  • Insulin or sulfonylureas (like gliclazide): adding a GLP-1 can cause low blood sugar. We ask your GP to adjust doses first.
  • The contraceptive pill: Mounjaro can reduce absorption. Use a barrier method for 4 weeks after starting and after each dose increase, or consider a non-oral method. Wegovy and Foundayo do not carry this warning.
  • Warfarin: dose changes need INR monitoring.
  • Thyroxine: absorption can shift. Your GP may recheck thyroid levels.

Why we verify your weight

UK pharmacy rules require independent weight evidence before a first prescription: a photo or video on the scales, or your GP record. It feels formal, but it is how a responsible pharmacy proves these medicines go to the people they are licensed for.

If you are not eligible

A no from us comes with an explanation and, where useful, a signpost. Options can include your GP, NHS weight management services, or simply waiting until circumstances change, after breastfeeding ends, for example. You are never charged for a declined request.

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Weight loss plans from £69 a month

Mounjaro, Wegovy, the Wegovy pill and the Foundayo pill. Each plan covers the medicine, prescriber review, monthly check-ins and tracked delivery.

See all plans

Check if treatment suits youFree health check. You pay nothing until a prescriber approves.

Check your eligibility

About this page

Written by
Able Clinic editorial team
Clinical review
Pharmacy team at Curb Healthcare Ltd, GPhC 9012581
Last reviewed

Each page is checked against the UK licence for the medicine. Read our editorial policy.

Sources

  1. Electronic medicines compendium: product information
  2. NICE: obesity identification, assessment and management (CG189)
  3. NHS: obesity treatment
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