Who Should Not Take Wegovy: Contraindications, Cautions and How to Decide

Hard stops: conditions where Wegovy is contraindicated

The clearest cases are the absolute contraindications written into Wegovy's licensed use. Anyone with a personal or family history of medullary thyroid carcinoma should not take semaglutide. The same applies to people diagnosed with Multiple Endocrine Neoplasia syndrome type 2, a genetic condition that increases thyroid cancer risk. These are not borderline cautions — they are categorical exclusions, regardless of BMI or other health factors.

Pregnancy sits in the same category. Wegovy is not recommended during pregnancy, while breastfeeding, or when a person is actively trying to conceive. The MHRA advises using contraception throughout treatment, and for a period afterwards before attempting to conceive. For women using oral contraceptive pills, NHS guidance adds a practical note specific to the injectable form of semaglutide: because GLP-1 medicines slow gastric emptying, pill absorption could theoretically be affected during the early weeks of a new treatment, though the evidence of a clinical effect is less clear-cut than with tirzepatide. Talking this through with a prescriber before starting is the right move.

Age is another firm boundary. Wegovy for weight management is licensed only for adults; the safety and efficacy data for under-18s simply isn't there. The semaglutide overview covers the licensed population in more detail if you want the full picture.

Serious cautions that need honest conversation with a prescriber

Beyond the hard stops, there is a second category: conditions that don't automatically rule out Wegovy but that a prescriber must think through carefully with you. Pancreatitis is the clearest example. The MHRA's January 2026 Drug Safety Update flagged acute pancreatitis as an infrequent but serious known risk with GLP-1 medicines, anyone with a previous episode should disclose this before starting, and the prescriber will weigh whether the treatment is appropriate. You can report suspected side effects and check the MHRA's communications on GLP-1 safety at the Yellow Card scheme.

Severe gastroparesis (delayed stomach emptying) is another condition that warrants real caution, because semaglutide itself slows gastric emptying and the two effects together can be problematic. Severe kidney or liver impairment, certain inflammatory bowel conditions, and a history of diabetic retinopathy are also areas where prescribers apply closer scrutiny before approving treatment.

None of this means treatment is impossible if you have one of these conditions, it means the clinical review is doing exactly the job it's supposed to do. Our clinical team reviews every consultation personally, not by algorithm, and these are the kinds of questions they are trained to resolve.

When the question is whether Wegovy fits your situation, not just your history

Some people who could technically take Wegovy still find it isn't the right fit right now. People taking medicines that carry a meaningful interaction risk (certain diabetes medicines that can cause hypoglycaemia when combined with semaglutide, for instance) need the prescriber to review the full list. The decision isn't always a yes or a no; sometimes it's a managed yes, with adjustments.

There's also the question of eligibility thresholds. The licensed starting point for Wegovy is a BMI of 30 or above, or 27 or above alongside a weight-related condition such as high blood pressure, type 2 diabetes or obstructive sleep apnoea. Lower BMI thresholds apply for some ethnic backgrounds under UK guidance. If you're close to those numbers, a prescriber can tell you definitively whether you meet the criteria, it's genuinely the quickest route to a clear answer, and reading through the key questions to ask yourself before taking Wegovy can help you prepare for that conversation. You might also find it useful to read about whether Wegovy is right for your situation before you decide.

Understanding the cost picture is part of the decision too. Wegovy is a private prescription at launch, so exploring all the available weight-loss treatment options first gives you a clearer sense of what you're choosing between.

What the consultation process actually checks

When you submit a consultation through a regulated online pharmacy, the prescriber is working through exactly this list: contraindications, relevant history, current medicines, BMI, and whether the benefit-to-risk balance makes sense for you specifically. At nume, your answers land with a GPhC-registered prescriber on the same day, a real clinician reading your notes, not a scoring system flagging fields.

If approved, your treatment arrives by tracked DPD delivery the next working day, in a plain box with nothing on the outside to indicate what's inside. The pen itself is pre-filled and pre-set; there's no measuring or assembly, though if you're wondering when to take your Wegovy shot each week, that's something your prescriber will also guide you on, and there's further detail on what time of day works best for taking Wegovy if you want to plan your routine in advance. But none of that matters if starting the medicine isn't clinically right for you, which is why who should not take semaglutide is the question worth answering before anything else. The NHS medicines page for semaglutide lists the contraindications and cautions in patient-level language if you want to cross-check anything here.

If you're ready to find out where you stand, check your eligibility through a free consultation, your prescriber can give you a definitive answer, usually the same day.