What is Foundayo?
Foundayo is Lilly's prescription-only tablet containing orforglipron, a GLP-1 receptor agonist. It acts on appetite regulation to help reduce hunger, supporting weight management alongside diet and physical activity.
It isn't a tablet version of Mounjaro: the two have different active ingredients. Nor is it interchangeable with Wegovy tablets.
Who may be eligible?
The UK licence for weight management is for adults with a starting BMI of at least 30, or at least 27 with a weight-related condition. When you're switching, your starting weight and treatment history matter too: a lower BMI after successful treatment doesn't tell the whole story.
How Foundayo tablets are taken
- Take your prescribed tablet once a day, at a time you can remember.
- Take it with or without food. There's no need to fast.
- Swallow it whole. Don't split, crush or chew it.
- Never take extra tablets to make a higher dose.
If you forget a dose, take it when you remember, but never more than one dose in a day. Ask your prescriber how to restart after a longer break.
Foundayo compared with Wegovy tablets
| Feature | Foundayo | Wegovy tablets |
|---|---|---|
| Active ingredient | Orforglipron | Semaglutide |
| Routine | Once daily | Once daily |
| Food and drink | No fasting needed | Empty stomach, a sip of water, then wait 30 minutes |
| Changing treatment | Individual prescriber plan | Individual prescriber plan |
Read our Wegovy tablets guide for more on that option.
Why consider switching?
Points to discuss
- A preference for tablets rather than needles
- How treatment fits work, travel and your routine
- Ongoing cost and your long-term plan
Reasons to review carefully
- Your current medicine works and you tolerate it
- You have troublesome symptoms or other medicines to consider
- Your appetite or weight could change during the transition
A tablet isn't automatically more effective or better tolerated. Your prescriber may recommend staying on the treatment you already use.
Planning the switch safely
Before your consultation, have your current medicine name, strength, last dose date, recent weight change and any side effects ready, along with any missed doses and all your other medicines or supplements.
Don't overlap treatments. Foundayo shouldn't be taken alongside another GLP-1 medicine such as Wegovy or Mounjaro. Get a clear stop date and start date from your prescriber.
The UK product information gives a Foundayo starting and dose-increase schedule, not an injection-to-tablet conversion chart. The gap after your last dose of another medicine is agreed individually.
Foundayo dose steps
Start with 0.8mg once daily. Allow at least 30 days at each step before increasing. After 2.5mg, further increases depend on your response and how well you tolerate it. The maximum is 17.2mg daily.
| Step | Once-daily dose | What happens next |
|---|---|---|
| 1 | 0.8mg | Starting dose; reviewed before increasing |
| 2 | 2.5mg | After at least 30 days on 0.8mg |
| 3 | 5.5mg | May follow at least 30 days on 2.5mg |
| 4 | 9mg | May follow at least 30 days on 5.5mg |
| 5 | 14.5mg | May follow at least 30 days on 9mg |
| 6 | 17.2mg | Maximum dose |
This is the dose sequence, not an instruction to increase every month. Follow your prescription and don't skip a step. See Foundayo prices by strength.
What your prescriber checks for your current treatment
| Current treatment | What your prescriber needs to check |
|---|---|
| Wegovy injections | Weekly dose, last injection, response and side effects, then when Foundayo can start |
| Mounjaro injections | Weekly dose, last injection, weight trend and any diabetes medicines. There's no milligram-for-milligram conversion |
| Wegovy tablets or other treatment | Exact medicine, daily dose and last dose, then a changeover without using two GLP-1 medicines together |
What does the research show?
The ATTAIN-1 trial studied 3,127 adults without diabetes over 72 weeks. At the highest dose studied, average weight loss was about 11% when people who stopped treatment were included, compared with about 2% on placebo. The often-quoted 12.4% comes from an analysis estimating results if everyone had continued treatment. Neither figure predicts an individual result.
The ATTAIN-MAINTAIN trial looked at switching to orforglipron after tirzepatide or semaglutide. It helped keep more of the earlier weight loss than placebo, though some weight was regained. It didn't compare switching with staying on an injection.
Side effects and when to get help
Nausea, vomiting, diarrhoea, constipation, indigestion and tummy discomfort can occur, especially when starting or increasing treatment. Tell your prescriber if symptoms persist or affect eating and drinking.
Severe, persistent tummy pain: stop taking Foundayo and get urgent medical help, especially if the pain spreads to your back or comes with vomiting. This can be a sign of pancreatitis.
Call 999 for difficulty breathing, collapse, or swelling of the tongue or throat.
Checks before starting
Tell your prescriber about pancreatitis, gallbladder problems, severe stomach-emptying problems, liver disease, diabetic eye disease, and any planned operation involving sedation. Give them a complete list of your medicines.
Pregnancy, breastfeeding and contraception
Don't take Foundayo during pregnancy or breastfeeding. If you're planning a pregnancy, discuss it first: UK guidance advises stopping at least three weeks before trying to conceive.
If you take an oral contraceptive, use a barrier method as well, or switch to a non-oral method, for 30 days after starting Foundayo and for 30 days after each dose increase.
Storage
Keep tablets in their original packaging to protect them from light, out of children's reach.
Talk it through with a prescriber
Start with our free online consultation. Before any treatment starts, you'll have a video consultation with a pharmacist or nurse prescriber, who will recommend what's safest for you.
Start free consultationFrequently asked questions
Can I switch from Mounjaro or Wegovy injections to Foundayo?
A switch may be considered after assessment. Agree your last injection date, Foundayo start date, dose and follow-up with your prescriber. Don't convert doses yourself.
Can I start on a higher Foundayo dose because I already use injections?
The licensed starting dose is 0.8mg once daily. Don't assume previous GLP-1 treatment lets you skip the starting plan; follow the prescription issued for you.
Do I have to wait seven days before starting?
Ask your prescriber for a specific start date. Timing depends on your previous medicine, your last dose and your circumstances.
Can I take Foundayo with another GLP-1 medicine?
No. Don't combine it with Wegovy, Mounjaro or another GLP-1 treatment.
Is Foundayo the same as Mounjaro in a tablet?
No. Foundayo contains orforglipron and Mounjaro contains tirzepatide. They are different medicines, both made by Lilly.
Will switching keep all my weight loss?
That can't be guaranteed. Review your appetite, weight trend and side effects with your prescriber after any change.
References
Last reviewed: October 2026. This guide is general information and doesn't replace advice from your prescriber or the leaflet supplied with your medicine.