Daily tablets and weekly injections offer different approaches to weight-loss treatment, although UK availability varies by medicine. If you’re looking to buy Mounjaro online, you’ll need an assessment by a qualified prescriber before a registered pharmacy can supply it.
This guide compares Foundayo and Mounjaro on results, side effects, convenience, cost and safety. It also explains what to look for in an online pharmacy and how to recognise an unregulated provider.
Key points
- Foundayo (orforglipron) is a once-daily tablet that can be taken at any time of day with no food or water restrictions. Mounjaro (tirzepatide) is a once-weekly injection.
- Average weight loss with Foundayo in its main trial was somewhat lower than has been seen with injectable semaglutide or tirzepatide. The trials were separate, so the comparison is indirect.
- Both need a prescription. Foundayo isn’t currently available on the NHS, and NHS access to Mounjaro is being phased in over up to 12 years.
- Buy only from a pharmacy you have checked yourself on the GPhC register.
What is the difference between weight-loss tablets and injections?
Weight-loss tablets are swallowed once a day. Weight-loss injections are given under the skin once a week.
Both belong to a group of medicines called GLP-1 receptor agonists. They copy a gut hormone that reduces appetite and slows how quickly the stomach empties. Mounjaro goes a step further, because tirzepatide activates two receptors, GIP and GLP-1.
The practical difference is how the medicine reaches your bloodstream. Semaglutide is a peptide that the gut would normally break down, so the Wegovy tablet relies on an absorption enhancer and a strict empty-stomach routine. Orforglipron is built differently. It is a small-molecule, non-peptide GLP-1 receptor agonist, which is why Foundayo doesn’t come with the same fasting rules.
Which weight-loss tablets and injections are available in the UK?
| Medicine | Active ingredient | Format | How often | UK status |
| Foundayo | orforglipron | Tablet | Once daily | Authorised by the MHRA on 10 August 2026 |
| Wegovy tablet | semaglutide | Tablet | Once daily | Approved by the MHRA on 11 June 2026 |
| Mounjaro | tirzepatide | Pen injection | Once weekly | NICE guidance published December 2024 |
| Wegovy | semaglutide | Pen injection | Once weekly | Authorised for weight management |
Older options exist too. Orlistat is a tablet that reduces fat absorption, and liraglutide (Saxenda) is a daily injection. Both tend to produce smaller average weight loss than the newer medicines.
Who can be prescribed them?
The Foundayo authorisation covers adults with a BMI of 30 or above, or a BMI between 27 and 30 with at least one weight-related condition, used alongside a reduced-calorie diet and more physical activity. The Wegovy tablet has the same thresholds, and Mounjaro’s private eligibility criteria match them. Typical qualifying conditions include type 2 diabetes, high blood pressure and sleep apnoea.
How well do weight-loss tablets and injections work?
Injections have produced larger average weight loss in trials, but tablets still deliver meaningful results for many people. The figures below come from different trials with different designs, so treat them as a rough guide rather than a league table.
| Medicine | Format | Trial | Average weight loss |
| Foundayo | Tablet | ATTAIN-1, 72 weeks | 11.2% on the highest dose, against 2.1% on placebo |
| Wegovy tablet | Tablet | OASIS 4, 64 weeks | 13.6% on the 25 mg dose |
| Mounjaro | Injection | SURMOUNT-5, 72 weeks | 20.2% at the maximum tolerated dose |
| Wegovy injection | Injection | SURMOUNT-5, 72 weeks | 13.7% at the maximum tolerated dose |
Averages hide a wide spread. Some people lose far more than the figure; others lose far less.
What did the Foundayo trial show?
ATTAIN-1 followed adults without diabetes who had obesity or overweight with a related condition, for 72 weeks. Among those who stayed on treatment as directed, the highest dose averaged 12.4% weight loss, and 59.6% lost at least a tenth of their body weight.
Side effects led 5.3% to 10.3% of people taking Foundayo stopping treatment, compared with 2.7% on placebo. The most common problems were digestive and mostly mild to moderate. Improvements in heart and metabolic risk markers were substantial, even though average weight loss was lower than with injectable options.
How does Mounjaro compare?
The best direct evidence is SURMOUNT-5, which randomly assigned 751 adults to tirzepatide or semaglutide injections for 72 weeks. More people on tirzepatide lost at least 10% of their body weight (81.6% against 60.5%) and at least 20% (48.4% against 27.3%).
Two caveats apply. The trial was open-label and funded by Eli Lilly, which makes Mounjaro.
Is a daily tablet or a weekly injection easier to live with?
It depends on your routine. The biggest practical gap is between Foundayo’s no-rules tablet and the Wegovy tablet’s fasting routine.
| Foundayo tablet | Wegovy tablet | Mounjaro injection | |
| Frequency | Once daily | Once daily | Once weekly |
| Food and drink rules | None, any time of day | Empty stomach, a small sip of water (up to 120 ml), then a 30-minute wait | None tied to meals |
| Needles | No | No | Yes, a small pen needle under the skin |
| Dose increases | Gradual, set by your prescriber | Starts at 1.5 mg, then 4 mg, 9 mg and 25 mg, at least a month on each | Starts low and steps up; each pen holds four weekly doses |
The Wegovy tablet also means waiting 30 minutes before taking other oral medicines, which is awkward if you take tablets first thing. A weekly injection removes daily decisions altogether, at the price of a needle.
What are the side effects and safety points?
Most side effects are digestive, and they tend to be most noticeable when you start or step up a dose.
- Digestive effects. Nausea, constipation and diarrhoea are the most commonly reported problems with Foundayo. Injections cause a similar pattern.
- Contraception and pregnancy. The MHRA says GLP-1 medicines shouldn’t be used during pregnancy, while trying to conceive or while breastfeeding, and that Mounjaro may make oral contraceptives less effective. It advises a barrier or non-oral method for four weeks after starting and after each dose increase. The US prescribing information for Foundayo gives similar advice for 30 days. Check the UK patient leaflet and ask your prescriber about your own method.
- Pancreatitis. The MHRA has highlighted acute pancreatitis as a rare but serious risk with this class of medicine. Severe stomach pain that doesn’t settle needs urgent medical help.
- Surgery. These medicines may raise the risk of stomach contents entering the lungs during anaesthesia or deep sedation, so tell the surgical team.
- Who needs extra care. Foundayo isn’t recommended for people with severe gastroparesis or severe liver disease. People with a history of thyroid cancer or MEN 2 shouldn’t use it. Prescribers should also ask sensitively about eating disorders.
- Reporting. Suspected side effects, or defective pens, can be reported through the Yellow Card scheme.
Can you buy Foundayo online in the UK?
Yes, but only with a prescription. Foundayo is a prescription-only medicine. It reached UK pharmacies on 24 August 2026, and for now it is available only on private prescription. A legitimate online pharmacy won’t supply it from a basket page. A prescriber has to assess you first.
A proper online route involves:
- A registered pharmacy. It should be registered with the General Pharmaceutical Council (GPhC). Look up its number on the GPhC register yourself.
- A real consultation. You’ll be asked about your medical history, current medicines, pregnancy plans and eating patterns.
- Independent checks. The prescriber can verify your weight, height or BMI by video consultation, in person, from your clinical records or through your GP. A phone call isn’t appropriate. Answers on an online questionnaire alone don’t meet the standard either.
- A decision that can go either way. Prescribers can and do decline when a medicine isn’t suitable.
- Proper supply and follow-up. The medicine arrives from the registered pharmacy in original packaging with the patient leaflet, and you know who to contact about side effects.
Stock, pricing and prescriber availability have shifted quickly since launch. Ask for the total cost and the follow-up plan before you pay.
Can you buy Mounjaro online safely in the UK?
Yes, through the same route: a GPhC-registered pharmacy, a prescriber’s assessment and a valid prescription. Mounjaro is a prescription-only medicine too.
The route matters because fakes exist. In February 2026, the MHRA reported falsified Mounjaro KwikPen 15 mg pens supplied through one UK online pharmacy. Testing found tirzepatide in the fake pens, but the MHRA couldn’t confirm the contents were sterile. It had no reports of patients needing treatment after using them. Check the strength and batch number printed on any pen you receive.
The MHRA has also warned against buying these medicines from unregulated sources such as beauty salons or social media and says a legitimate pharmacy is the only way to be sure the product is genuine.
How can you tell a legitimate online pharmacy from a risky one?
| Reassuring signs | Warning signs |
| A GPhC registration number that matches the register | No registration details, or a number that doesn’t match |
| A prescriber who checks your height and weight by video, records or your GP | A checkout that only needs a questionnaire |
| Questions about health history, medicines, pregnancy plans and eating patterns | No medical questions, or you simply pick your own dose. |
| Clear costs, including consultation, delivery and follow-up | A price far below every other provider |
| Original manufacturer packaging with batch numbers | Unlabelled vials, “research” products, or sales through social media |
| Reviews as your dose changes | Discount codes, referral links and pressure to buy now; advertising prescription-only weight-loss medicines to the public is against UK rules. |
How much do weight-loss tablets and injections cost in the UK?
Private prices depend on the medicine, the dose and the provider, and they change often. As of late September 2026:
- Foundayo: Lilly said the UK monthly cost would sit between £100 and £120, noticeably below Mounjaro.
- Mounjaro: independent price guides put a pen at roughly £130 to £340 depending on dose and provider. Lilly raised its UK list price on 1 September 2025.
Each Mounjaro pen holds four weekly doses, so the pen price is close to your monthly cost. Your ongoing spend then follows the maintenance dose you settle on. When comparing offers, check whether the price includes the consultation, pen needles, a sharps bin and delivery.
Can you get weight-loss tablets or injections on the NHS?
Mounjaro, in a limited way. NICE recommended tirzepatide for weight management in December 2024, and the rollout is phased over up to 12 years. GP prescribing is currently restricted to people with a very high BMI and several qualifying health conditions. Most UK patients who take tirzepatide still get it privately.
The tablets aren’t on the NHS yet. The MHRA has said the Wegovy tablet isn’t currently available through the NHS. For Foundayo, wider NHS availability depends on a NICE assessment, and Lilly says it is working with the agency. Ask your GP whether you might qualify.
How do you choose between a tablet and an injection?
Use these as prompts for your consultation, not as a recommendation.
- Dislike needles or want simplicity: a tablet may suit you, and Foundayo has no mealtime rules.
- Want the largest average weight loss: trial averages are higher with injectable tirzepatide, so ask about it.
- Take other tablets in the morning, or work shifts: a fasting-based tablet can be awkward. A weekly injection or Foundayo may fit better.
- Use the contraceptive pill or plan a pregnancy: it affects your options with both formats.
- Watching the budget: compare the total monthly cost at your dose, not the headline price.
- Thinking long term: weight often returns after stopping, so ask what the plan is beyond the first few months.
Frequently asked questions
Is Foundayo available in the UK?
Yes. The MHRA authorised it on 10 August 2026, and it launched on private prescription on 24 August 2026.
Is Foundayo as effective as Mounjaro?
On average, probably not, judging by separate trials. Foundayo’s highest dose averaged 11.2% weight loss over 72 weeks, while Mounjaro reached 20.2% in SURMOUNT-5. The trials differ, and individual results vary.
Do I need a prescription to buy Mounjaro online?
Yes. A GPhC-registered pharmacy should only supply it if the prescriber has held an appropriate consultation and has all the information needed to judge it safe and suitable.
Can I take Foundayo if I use the contraceptive pill?
Possibly, but you may need extra protection. The US prescribing information advises a non-oral or barrier method for 30 days after starting and after each dose increase. Your UK leaflet and prescriber have the final say.
Is Foundayo on the NHS?
Not currently.
What happens if I stop taking it?
Weight often returns after stopping any of these medicines. Ask your prescriber about a long-term plan before you begin.
Can I switch from an injection to a tablet?
Only with a prescriber’s guidance. Doses aren’t interchangeable between products, and the tablets come with different instructions.