Are tablets or injections better for weight loss?

Step 1, understand what you're actually comparing

The question of tablets versus injections for weight loss is relatively new. Until summer 2026, every licensed GLP-1 weight-loss medicine in the UK was an injection. On 11 June 2026, the MHRA approved Wegovy tablets (oral semaglutide co-formulated with an absorption enhancer) making the UK the first country in Europe to licence an oral GLP-1 specifically for weight management. So the comparison now is between three medicines across two formats: Mounjaro (tirzepatide, injection), Wegovy injection (semaglutide 2.4mg or the newer 7.2mg dose), and Wegovy tablets (oral semaglutide, 25mg maintenance dose).

Each medicine has its own mechanism. Mounjaro activates two gut-hormone receptors (GIP and GLP-1) making it the only dual-agonist weight-loss medicine licensed in the UK. Wegovy in both its injection and tablet forms works on the GLP-1 receptor only. Format affects absorption and convenience; the underlying pharmacology still differs. More on how GLP-1 injections work is covered separately if you want the mechanism detail.

Knowing which medicine is in which format matters before making any comparison. "Injections" is not one product, and "tablets" is not one product. The right starting point is what each is, then how it performs.

Step 2, look at what the trial evidence actually says about results

Injections currently lead on average weight loss in published trials. In the SURMOUNT-1 study, tirzepatide at its highest dose produced an average body-weight reduction of around 20–21% over 72 weeks in adults with obesity. The STEP 1 trial for semaglutide 2.4mg injection showed approximately 15% average reduction over 68 weeks. A newer 7.2mg semaglutide dose, approved by the MHRA in April 2026, brought that figure closer to around 20.7% in trials, a detailed comparison of injection results covers that evidence.

The Wegovy tablet trial (OASIS 4, 64 weeks, 307 adults with obesity or overweight plus at least one weight-related condition) reported an average weight loss of around 13.6% versus approximately 2.4% on placebo. Among participants who stayed fully adherent to the tablet regimen throughout the trial, the figure rose to around 16.6%. That is a meaningful result, and meaningfully lower than the injection figures on a straight comparison. The NHS overview of semaglutide covers what the medicine is and how it works at the patient level.

These are average figures from controlled trials. Individual results vary considerably. Adherence, lifestyle changes alongside treatment, and tolerance of side effects all shift outcomes in real life. A trial average answers a population question, not a personal one.

Step 3, weigh the practical differences that affect adherence

For many people, the practical fit of a medicine matters as much as its trial headline. Injections arrive as pre-filled pens stored in the fridge; the pen delivers a once-weekly dose by pressing against the skin and activating. When your pen arrives from our pharmacy in its plain DPD box, it goes straight into the fridge door and stays there for the week. Some people find once-weekly easy to build into a routine. Others find the injection itself a barrier, even with the auto-injector design.

The Wegovy tablet is taken once daily, first thing in the morning on an empty stomach, with a small amount of plain water, then a 30-minute wait before food or other medicines. No refrigeration. That makes it straightforwardly travel-friendly and removes any needle concern entirely. The trade-off is daily rather than weekly administration, and the morning timing restriction is a real constraint for some routines. You can read more about the practical side of tablets versus injections if that comparison is your main question.

Side effects for both formats are broadly similar in character, predominantly gastrointestinal, including nausea, loose stools, and indigestion, most noticeable when starting treatment or after a dose increase. The tablet trial reported gastrointestinal side effects in roughly 74% of participants, compared to around 42% on placebo; these were mainly mild to moderate and tended to settle. The side-effect profile of weight-loss injections follows a comparable pattern. Knowing this in advance, rather than being surprised by it, is one reason clinical review before starting matters.

Cost is also a practical factor. Private weight-loss treatment is priced per pen or per month, and prices vary by medicine, dose, and provider. A fuller breakdown of what weight-loss injections cost privately in the UK gives honest context, including what a quoted price should cover. The NICE appraisal of tirzepatide (TA1026) gives a sense of the NHS eligibility thresholds if you want to understand whether the NHS route applies to your situation.

Step 4, what a prescriber considers when helping you decide

A prescriber reviewing your case looks at more than trial averages. Your BMI, any weight-related conditions, your medication history, how you've responded to previous treatments, your daily routine, and your own preference all feed into the recommendation. Mounjaro is licensed for adults with a BMI of 30 or above, or 27 or above alongside a weight-related condition such as high blood pressure or type 2 diabetes. The Wegovy tablet holds the same thresholds. Wegovy injection carries a similar profile. Lower BMI thresholds apply for some ethnic backgrounds under UK guidance.

There is no universal answer to whether weight loss tablets or injections are better, the evidence favours injections on average results right now, but adherence, tolerability, and lifestyle fit can make a tablet the right clinical choice for a specific person. Our prescribers work through exactly this kind of decision with patients every day. Choosing between the injection options is a related question our clinical team covers if you are already leaning that way.

If you want to understand the options across the full range of treatments before deciding, the weight-loss treatment overview is a good place to start. And if you want a prescriber to review your individual situation, you can speak to our prescribers through a free consultation, no referral needed, reviewed the same working day by a real clinician.