Weight loss medication in the UK has moved well beyond a single option.
Mounjaro, Wegovy, and now Foundayo all work on similar hormone pathways to reduce appetite, but they’re taken differently, dosed differently, and were tested in different clinical trials.
There’s also a genuinely new choice as of 2026: Wegovy is no longer injection-only, and Foundayo is the first weight loss tablet with no food or water restrictions at all.
This guide compares the four options McMinns Pharmacy is asked about most: Mounjaro, the Wegovy injection, the Wegovy tablet, and Foundayo.
It’s here to help you understand the practical differences before your consultation, not to tell you which one to choose – that’s a decision for you and your prescriber, based on your health, your goals, and what fits your life.
The Options at a Glance
- Mounjaro (tirzepatide) – a once-weekly injection that acts on two gut hormones (GIP and GLP-1) rather than one.
- Wegovy injection (semaglutide) – a once-weekly injection, the original and most established option of the four.
- Wegovy tablet (semaglutide) – a once-daily tablet approved by the MHRA in June 2026, taken on a strict fasting routine.
- Foundayo (orforglipron) – a once-daily tablet approved by the MHRA in August 2026, with no fasting or water restrictions.
Comparing Results: What the Clinical Trials Showed
Each medicine has been tested in its own clinical trial programme, at its own highest studied dose, over slightly different timeframes.
There’s no single trial that pits all four against each other directly, so treat these as a general guide to what’s been demonstrated, not a guarantee of what any individual will achieve.
Real-world results vary from person to person and depend on dose, diet and activity alongside the medicine.
| Medicine | Trial | Duration | Average weight loss (highest dose vs placebo) |
| Mounjaro | SURMOUNT-1 | 72 weeks | 22.5% vs 2.4% on placebo (15mg dose) |
| Wegovy injection | STEP 1 | 68 weeks | ~14.9% vs ~2.4% on placebo (2.4mg dose) |
| Wegovy tablet | OASIS 4 | 64 weeks | 14% vs 2% on placebo (25mg dose) |
| Foundayo | ATTAIN-1 | 72 weeks | 11.2% vs 2.1% on placebo (highest dose) |
Broadly, the injectable options have shown the largest average reductions in these trials, with Mounjaro’s dual-hormone action producing the highest figures recorded so far.
That doesn’t automatically make it the right choice for everyone; how well a medicine fits your routine affects how consistently you take it, which matters just as much as the headline trial figure.
Food and Drink Restrictions
- Mounjaro – none. Can be injected at any time of day, with or without food.
- Wegovy injection – none. Can be injected at any time of day, with or without food.
- Wegovy tablet – strict rules. Taken on an empty stomach after at least 8 hours without food, swallowed with no more than 120ml of water, then a wait of at least 30 minutes before eating, drinking anything else, or taking other oral medicines.
- Foundayo – none. Can be taken at any time of day, with or without food or water, and this flexibility is one of the main things that sets it apart from the Wegovy tablet.
Dosing: How Often and How Much
All four start at a low dose and are increased gradually, usually reviewed roughly every four weeks, to reduce side effects and let your body adjust.
| Medicine | Frequency | Starting dose | Titration |
| Mounjaro | Weekly | 2.5mg | Increases in 2.5mg steps roughly every 4 weeks, up to a maximum of 15mg |
| Wegovy injection | Weekly | 0.25mg | Increases roughly every 4 weeks (0.25 → 0.5 → 1 → 1.7mg) to a 2.4mg maintenance dose |
| Wegovy tablet | Daily | 1.5mg | Increased under your prescriber’s guidance over several months to a maintenance dose they’ll confirm with you |
| Foundayo | Daily | 0.8mg | Increases roughly every 4 weeks, up to a maximum of 17.2mg |
Never adjust your own dose. If you’re unsure what strength you should be on, or you’re thinking about switching between any of these medicines, speak to your prescriber or pharmacist first.
How Each Medication Is Taken
- Mounjaro – injected under the skin (abdomen, thigh, or upper arm) using a pre-filled pen, once a week.
- Wegovy injection – injected under the skin (abdomen, thigh, or upper arm) using a pre-filled pen, once a week.
- Wegovy tablet – swallowed whole with a sip of water, once a day, following the fasting routine above. Never split, crush or chew it.
- Foundayo – swallowed whole, once a day, at any time that suits you. Never split, crush or chew it.
Storage
- Mounjaro – keep refrigerated (2–8°C) before first use. Once in use, it can be kept below 30°C or in the fridge for up to 30 days.
- Wegovy injection – keep refrigerated (2–8°C) before first use. Once in use, it can be kept below 30°C or in the fridge for up to 6 weeks.
- Wegovy tablet – no fridge needed. Keep in the original blister pack, away from light and moisture.
- Foundayo – no fridge needed. Keep in the original packaging, away from light, as the tablets are light-sensitive.
Which Option Might Suit You?
There’s no single “best” medication here; the right one depends on your health history, what you’re aiming for, and how each option fits into daily life. A few practical questions worth thinking about before your consultation:
- Would you rather manage a weekly injection or a daily tablet?
- Does your routine realistically allow for an 8-hour fast and a 30-minute wait each morning, or would a no-restriction tablet or injection suit you better?
- Do you have any needle anxiety, or a preference either way?
- Do you have other health conditions, such as type 2 diabetes, that might make one option more suitable than another?
Eligibility for all four is broadly similar: adults with a BMI of 30 or above, or a BMI of 27–29.9 with a weight-related health condition such as type 2 diabetes, high blood pressure or cardiovascular disease. All should be taken alongside a reduced-calorie diet and increased physical activity.
A full clinical assessment is needed to confirm which, if any, is suitable for you.
Frequently Asked Questions
Which weight loss medication is most effective?
Trial results can’t be compared directly since each medicine was tested separately, at different doses and over different timeframes. Mounjaro has shown the highest average results recorded so far, but effectiveness for any individual depends on far more than the headline trial figure, including how consistently the medicine fits your routine.
Can I switch between these medicines?
Potentially, but only under the guidance of your prescriber, who can advise on timing and dosing when moving between them.
Are any of these available on the NHS?
Mounjaro and the Wegovy injection are available through the NHS in some circumstances, subject to eligibility criteria that vary by area and are reviewed regularly. The Wegovy tablet and Foundayo are currently private prescription only, with NHS reviews pending. Ask us for the current position.
Talk to McMinns Pharmacy About Your Options
Choosing between a weekly injection and a daily tablet, or between the different medicines available, is easier with someone who can talk it through with you.
Our pharmacy team can go through your health history, your goals and your day-to-day routine, and help you understand which options are realistic for you.
Contact the McMinns Pharmacy team to discuss your options.