The US label for Foundayo (orforglipron) lists nausea, constipation, diarrhoea and vomiting as its most common side effects (US label). In the label's pooled weight-management trials, 8% of people on it stopped because of side effects, against 3% on placebo (US label). It is approved in the United States and the United Kingdom, but it is not registered in Singapore (Drugs@FDA; MHRA; HSA register). GetLean does prescribe and supply HSA-registered GLP-1 medications, with daily WhatsApp coaching between reviews.
Availability in Singapore. This medicine is not available in Singapore. It is not registered with the Health Sciences Authority, so no doctor here can prescribe it and there is no legitimate local supply. Anything offered under this name in Singapore is coming from outside the regulated system, and what that actually means is set out here.
What are the side effects of Foundayo?
Table 1 of the US label pools two placebo-controlled trials of adults with obesity or overweight (3,155 people on Foundayo, 1,576 on placebo, up to 72 weeks). Of the 13 reactions it lists, the eight most common are below, at the highest of the label's three doses.
| Side effect | Highest dose | Placebo |
|---|---|---|
| Nausea | 35% | 10% |
| Diarrhoea | 25% | 11% |
| Constipation | 24% | 9% |
| Vomiting | 24% | 4% |
| Abdominal pain | 14% | 7% |
| Indigestion (dyspepsia) | 13% | 4% |
| Headache | 9% | 7% |
| Fatigue | 9% | 4% |
US label, Table 1 (US label). The label cautions that rates in one medicine's trials cannot be directly compared with rates in another's.
Hair loss (5% at the highest dose against 2% on placebo) was reported more often by women (7%) than men (0.9%) on Foundayo, and the label links it to weight reduction.
Stomach and gut reactions of any kind were reported by 60%, 68% and 69% of people across the three doses, against 37% on placebo. The label says nausea, vomiting and diarrhoea were more frequent while the dose was being raised and decreased over time. Tachycardia (a faster heartbeat) was reported by 3% of people on Foundayo and 0.9% on placebo.
The boxed warning and other warnings
These are the US label's words; Foundayo has no Singapore label. The boxed warning is headed "WARNING: RISK OF THYROID C-CELL TUMORS" and its first paragraph reads:
In products with glucagon-like peptide-1 (GLP-1) receptor agonist activity that are pharmacologically active in rats and mice, rodent thyroid C-cell tumors (adenomas and carcinomas) have been observed at clinically relevant exposures and are considered GLP-1 receptor-dependent effects in rodents. Orforglipron is not pharmacologically active in rats or mice and did not produce tumors in rodents [see Nonclinical Toxicology (13.1)]. While orforglipron is pharmacologically active at the human GLP-1 receptor, the human relevance of GLP-1 receptor-dependent thyroid C-cell tumors observed in rodents has not been determined [see Warnings and Precautions (5.1), Nonclinical Toxicology (13.1)]. (US label)
The label contraindicates Foundayo in people with a personal or family history of medullary thyroid carcinoma or multiple endocrine neoplasia syndrome type 2, and in people with a known serious hypersensitivity to orforglipron or any of its excipients. Its other warnings and precautions are headed: acute pancreatitis; severe gastrointestinal reactions; acute kidney injury due to volume depletion (reported "in some cases requiring hemodialysis"); hypoglycemia; hypersensitivity reactions; diabetic retinopathy complications in patients with type 2 diabetes; acute gallbladder disease; and pulmonary aspiration during general anesthesia or deep sedation.
Stopping because of side effects
Across the label's two pooled trials, 8% of people on Foundayo (6%, 9% and 10% across the three doses) permanently stopped treatment because of adverse reactions, against 3% on placebo.
What the trials showed
ATTAIN-1, ATTAIN-2, ACHIEVE-3 and ATTAIN-MAINTAIN were funded by Eli Lilly; doses are described here as the lowest, middle and highest studied. ATTAIN-1 randomised 3,127 adults with obesity and without diabetes (Wharton 2025), and ATTAIN-2 randomised 1,613 adults with obesity or overweight and type 2 diabetes (Horn 2025), to one of three doses of once-daily orforglipron or to placebo, for 72 weeks.
| Dose studied | ATTAIN-1 (no diabetes) | ATTAIN-2 (type 2 diabetes) |
|---|---|---|
| Lowest dose | −7.5% | −5.1% |
| Middle dose | −8.4% | −7.0% |
| Highest dose | −11.2% | −9.6% |
| Placebo | −2.1% | −2.5% |
Average weight change at 72 weeks. Treatment-regimen estimand, counting everyone randomised (Wharton 2025; Horn 2025). Individual results vary and are not guaranteed.
In ATTAIN-1, 54.6% of people on the highest dose lost at least 10% of their body weight, against 12.9% on placebo (Wharton 2025). Between 5.3% and 10.3% of those on orforglipron stopped because of side effects, against 2.7% on placebo, and the most common side effects were digestive and mostly mild to moderate (Wharton 2025). In the US label's description of the two trials, 28% of participants in ATTAIN-1 and 17% in ATTAIN-2 were Asian, and its results tables are not broken down by race (US label).
ACHIEVE-3 compared orforglipron with oral semaglutide, open-label, in 1,698 adults with type 2 diabetes for 52 weeks; its main result was HbA1c, a blood-sugar measure, not weight (Rosenstock 2026). HbA1c fell by 1.71% and 1.91% on the two orforglipron doses and by 1.23% and 1.47% on the two oral semaglutide doses, and orforglipron was reported as non-inferior and superior on that measure. Stomach and gut events (59% and 58% against 37% and 45%) and stopping because of side effects (9% and 10% against 4% and 5%) were higher on orforglipron; individual results vary.
In ATTAIN-MAINTAIN, adults who had lost weight on tirzepatide (205) or semaglutide (171) were randomised to orforglipron or placebo; among those at a weight plateau, orforglipron kept a model-based 74.7% and 79.3% of the weight reduction at week 52, against 49.2% and 37.6% on placebo (Aronne 2026). It had no arm continuing the injection and lasted one year, and individual results vary. The overview of what is coming sets these figures beside the trial results of other medicines in development.
How it is taken where it is approved
The UK authorisation describes a tablet taken once a day, at any time of day, with no food or water restrictions (MHRA). The US label says once daily, with or without food, with doses raised in steps to reduce the risk of stomach and gut reactions (US label). The US label indicates it, with a reduced-calorie diet and more physical activity, to reduce excess weight and keep it off in adults with obesity, or overweight with at least one weight-related condition (DailyMed).
When could Foundayo be registered in Singapore?
It was approved in the United States on 1 April 2026 (Drugs@FDA) and authorised in the United Kingdom on 10 August 2026, for weight management and for type 2 diabetes (MHRA). An approval elsewhere does not register a medicine here; that is a separate decision by the Health Sciences Authority.
HSA's abridged route covers a product approved by at least one drug regulatory agency, its verification route one approved by at least two of its reference agencies, a list that includes the FDA and the MHRA (HSA routes). HSA's published target times for a new drug application are 50 working days for screening, then 60 for evaluation on the verification route, 180 on the abridged route and 270 on the full route, not counting the applicant's time to answer HSA's questions (HSA fees).
Those times begin when a company applies, and none of the sources used for this page says whether an application has been made in Singapore. This page therefore gives no date, and nothing on it should be read as a sign that one is near. No product named Foundayo, and none containing orforglipron, is on Singapore's register of therapeutic products (HSA register) or among the new drugs HSA approved from January to September 2026 (HSA approvals), checked 14 October 2026. If it is ever registered in Singapore, the indication it carries here will be whatever HSA approves, which need not match the US or UK label. Retatrutide and orforglipron are not registered in Singapore, and GetLean does not prescribe or supply them. GetLean does prescribe and supply HSA-registered GLP-1 medications, after a consultation with Dr Quek.
Foundayo in Singapore covers its status here and how it differs from the tablet that is registered, and the grey-market warning covers anything offered under this name.
Read the transcript
What are the side effects of Foundayo, or orforglipron?
Digestive ones lead the list. The US label gives nausea, constipation, diarrhoea and vomiting as the most common.
I'm Dr Quek, a Singapore-registered doctor, and the doctor behind the GetLean GLP-1 Taper Plan.
Retatrutide and orforglipron are not registered in Singapore, and GetLean does not prescribe or supply them.
How common are they?
In the US label's pooled trials of adults with obesity or overweight, nausea hit thirty-five in a hundred people on the highest dose, against ten on placebo.
The label says nausea, vomiting and diarrhoea were more frequent while the dose was being raised, and decreased over time.
What about hair loss?
Hair loss was five in a hundred at the highest dose, against two on placebo. The label links it to weight reduction.
Did side effects make people stop?
Across the label's two pooled trials, eight in a hundred on Foundayo permanently stopped because of adverse reactions, against three on placebo.
In a trial of more than three thousand adults with obesity and no diabetes, the most common side effects were digestive, and mostly mild to moderate.
Does Foundayo have a boxed warning?
Yes: the US label carries a boxed warning headed risk of thyroid C-cell tumours.
In rats and mice, thyroid tumours have been observed with GLP-1 medicines that are active in those animals, but orforglipron isn't active in rats or mice, and it didn't produce tumours in rodents.
But it is active at the human GLP-1 receptor, and the label says the human relevance of those rodent findings has not been determined.
When could Foundayo be available in Singapore?
It's approved in the United States and the United Kingdom, but an approval elsewhere doesn't register a medicine here.
That's a separate decision by the Health Sciences Authority, and none of the sources we used says whether an application has been made here.
So I can't give you a date.
If you're considering GLP-1 medication to reach your weight goal, and you'd like to taper off it one day, I invite you to visit getleanclinic.sg to learn about our approach and the GetLean GLP-1 Taper Plan.
Common questions
What are the most common side effects of Foundayo?
In the US label's pooled weight-management trials, nausea was reported by 35% of people at the highest dose against 10% on placebo, diarrhoea by 25% against 11%, constipation by 24% against 9% and vomiting by 24% against 4% (US label).
Does Foundayo have a boxed warning?
Yes. The US label carries a boxed warning headed “WARNING: RISK OF THYROID C-CELL TUMORS”, which says that “the human relevance of GLP-1 receptor-dependent thyroid C-cell tumors observed in rodents has not been determined” (US label).
What did the main Foundayo (orforglipron) trials show?
In ATTAIN-1, average weight change at 72 weeks was −7.5%, −8.4% and −11.2% across the lowest, middle and highest doses studied, against −2.1% on placebo (Wharton 2025). Individual results vary and are not guaranteed.
When will Foundayo be available in Singapore?
This page cannot give a date: Foundayo is not registered in Singapore, and none of the sources used here gives a date for it (HSA register; HSA approvals).