Tirzepatide is a once-weekly injectable peptide made by Eli Lilly. It activates the receptors for two gut hormones: glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1). It is sold as Mounjaro for type 2 diabetes and as Zepbound for weight management and obstructive sleep apnea.
It is a fully approved drug backed by large trials. At the highest dose, 15 mg/week, adults with obesity lost an average of 20.9% of their body weight over 72 weeks, compared with 3.1% on placebo. In a head-to-head trial it produced more weight loss than semaglutide. As with other drugs in this class, most of the lost weight comes back when treatment stops, and about a quarter of the weight lost is lean mass.
This page summarizes what the FDA labels, the clinical trials and regulators report. It is for education only and is not medical advice.
| Property | Detail |
|---|---|
| Drug class | Dual GIP and GLP-1 receptor agonist (fatty-acid-modified peptide) |
| Brands / first US approval | Mounjaro (May 13, 2022); Zepbound (November 8, 2023); Zepbound for sleep apnea (December 20, 2024) |
| Route | Subcutaneous injection once weekly |
| Labeled doses | Start at 2.5 mg/week; increase by 2.5 mg at least every 4 weeks; maintenance 5, 10 or 15 mg/week; maximum 15 mg/week (10 mg/week in children with diabetes) |
| Half-life (label) | About 5 days (5–6 days in people with obesity) |
| Bioavailability (label) | 80%; peak level about 24 hours after injection (range 8–72 hours) |
| Boxed warning | Thyroid C-cell tumors in rats; contraindicated with a personal or family history of medullary thyroid carcinoma or MEN 2 |
| US status | Prescription-only drug; FDA declared the tirzepatide injection shortage resolved (October 2024, reaffirmed December 19, 2024) |
| WADA status | Not prohibited; markers of tirzepatide are on the 2026 Monitoring Program |
What it is
Tirzepatide is a 39-amino-acid linear peptide whose sequence is based on human GIP. Its formula is C₂₂₅H₃₄₈N₄₈O₆₈ and its molecular weight is 4813.53 Da (Zepbound label; Coskun et al., Mol Metab 2018). Lilly developed it under the code name LY3298176.
| Structural feature | What the label and discovery paper report |
|---|---|
| GIP-based 39-amino-acid backbone | Binds and activates both the GIP and the GLP-1 receptor |
| Aminoisobutyric acid (Aib) at positions 2 and 13 | Two non-natural amino acids built into the sequence |
| C20 fatty di-acid attached to lysine 20 through a linker | Binds the drug to albumin, the main blood protein, which prolongs the half-life |
| Amidated C-terminus | Part of the final molecule’s design |
In cell-based binding tests, tirzepatide bound the GIP receptor about as strongly as natural GIP, but bound the GLP-1 receptor about 5 times more weakly than natural GLP-1 (Coskun et al., Mol Metab 2018). In mice, it reduced food intake and body weight more than a GLP-1 receptor agonist alone. These are laboratory and animal findings. The human comparisons are the head-to-head trials described below.
According to the labels, tirzepatide:
- raises insulin release only when blood glucose is high, and lowers glucagon (15 mg reduced fasting glucagon by 28% and glucagon after a meal by 43% at 28 weeks);
- improves insulin sensitivity, shown in a clamp study after 28 weeks;
- slows stomach emptying, most strongly after the first dose, with the effect fading over time;
- reduces calorie intake, likely through appetite, via GIP and GLP-1 receptors in brain areas that regulate eating.
The Zepbound label states that it lowers body weight “with greater fat mass loss than lean mass loss.”
Pharmacokinetics
From the Mounjaro and Zepbound labels (Mounjaro label; Zepbound label):
| Parameter | Value |
|---|---|
| Absolute bioavailability | 80% |
| Time to peak | Median 24 hours (range 8–72 hours) |
| Albumin binding | 99% |
| Volume of distribution | About 10 L |
| Clearance | About 0.06 L/h |
| Elimination half-life | About 5 days; 5–6 days in people with overweight, obesity or sleep apnea |
| Steady state | After 4 weeks of weekly dosing |
| Intact drug in urine or feces | None detected |
The body breaks tirzepatide down by cutting up the peptide chain, breaking down the fatty chain (beta-oxidation) and splitting the amide bond. Its metabolites leave in urine and feces. Kidney impairment, including end-stage kidney disease, and liver impairment did not change its kinetics, and the labels call for no dose adjustment.
Exposure rises in proportion to dose. In the first human study, the mean half-life was 116.7 hours, about 5 days, which supported once-weekly dosing (Coskun et al., Mol Metab 2018).
Most people develop antibodies to the drug. In the weight trials, 64.5% of Zepbound-treated patients had anti-tirzepatide antibodies. Neutralizing antibodies were uncommon (under 3%). The label found no effect on blood levels or effectiveness. Patients with antibodies did have more injection-site and allergic-type reactions.
Approved medical use
| Product | US-approved uses | Labeled maintenance dose |
|---|---|---|
| Mounjaro | Blood sugar control in adults and children 10 and older with type 2 diabetes; lowering major cardiovascular events in adults with type 2 diabetes at high risk | Up to 15 mg/week in adults; up to 10 mg/week in children |
| Zepbound | Weight reduction and long-term maintenance in adults with obesity, or overweight plus at least one weight-related condition; moderate to severe obstructive sleep apnea in adults with obesity | 5, 10 or 15 mg/week for weight; 10 or 15 mg/week for sleep apnea |
Both products start at 2.5 mg once weekly for 4 weeks. The 2.5 mg dose is only for starting treatment. The dose then rises in 2.5 mg steps, at least 4 weeks apart, to reduce stomach side effects. Zepbound is used together with a reduced-calorie diet and increased physical activity.
A missed dose can be taken within 4 days. After that it should be skipped. The labels say not to combine tirzepatide with other tirzepatide products or with any GLP-1 receptor agonist (Zepbound label; FDA, 2023; FDA, 2024).
What the research shows
Weight loss
All the main weight trials paired tirzepatide or placebo with diet and activity counseling. They enrolled adults with a BMI of 30 or higher, or 27 or higher with a weight-related condition:
| Trial | n | Duration | Dose | Weight change on tirzepatide | Comparator |
|---|---|---|---|---|---|
| SURMOUNT-1, no diabetes (Jastreboff et al., NEJM 2022) | 2,539 | 72 weeks | 5, 10 or 15 mg/week | −15.0%, −19.5%, −20.9% | Placebo −3.1% |
| SURMOUNT-2, type 2 diabetes (Zepbound label) | 938 | 72 weeks | 10 or 15 mg/week | −12.8%, −14.7% | Placebo −3.2% |
| SURMOUNT-3, after a 12-week intensive diet lead-in (Zepbound label) | 579 | 72 weeks | 10 or 15 mg/week | −18.4% further loss | Placebo +2.5% |
| SURMOUNT-5, vs semaglutide, open-label (Aronne et al., NEJM 2025) | 751 | 72 weeks | 10 or 15 mg/week | −20.2% | Semaglutide 1.7 or 2.4 mg/week −13.7% |
In SURMOUNT-1, 50% of the 10 mg group and 57% of the 15 mg group lost at least 20% of their body weight, compared with 3% on placebo. Side effects led to stopping treatment in 4.3–7.1% of tirzepatide groups and 2.6% on placebo.
People with type 2 diabetes lost less weight, as with other drugs in this class. In SURMOUNT-3, participants first lost an average of 6.9% through intensive diet and exercise, then lost another 18.4% on tirzepatide.
In SURMOUNT-5, waist size fell by 18.4 cm on tirzepatide and 13.0 cm on semaglutide. The trial was open-label, meaning participants knew which drug they were taking.
What happens after stopping
SURMOUNT-4 tested withdrawal directly (Aronne et al., JAMA 2024). 783 adults took tirzepatide at the highest tolerated dose (10 or 15 mg) for 36 weeks and lost an average of 20.9%. Then 670 were randomized to continue the drug or switch to placebo for another 52 weeks:
| Outcome | Continued tirzepatide | Switched to placebo |
|---|---|---|
| Weight change, week 36 to 88 | −5.5% | +14.0% |
| Kept at least 80% of the earlier weight loss | 89.5% | 16.6% |
| Total weight change, week 0 to 88 | −25.3% | −9.9% |
In the placebo group, waist size, blood pressure, cholesterol and blood sugar also moved back toward their starting values (Zepbound label). The authors concluded that stopping tirzepatide led to substantial weight regain.
Three years and diabetes prevention
Within SURMOUNT-1, 1,032 participants also had prediabetes and stayed on their assigned treatment for 176 weeks, about 3.4 years (Jastreboff et al., NEJM 2025):
- Weight change: −12.3% (5 mg), −18.7% (10 mg) and −19.7% (15 mg), compared with −1.3% on placebo.
- New type 2 diabetes: 1.3% on tirzepatide vs 13.3% on placebo (hazard ratio 0.07).
- After 17 weeks off treatment: 2.4% vs 13.7% had type 2 diabetes (hazard ratio 0.12).
Lean mass and muscle
Any large weight loss includes some lean mass (muscle, organs, water and other non-fat tissue). In a SURMOUNT-1 substudy, 160 participants had body-composition (DXA) scans at baseline and week 72 (Look et al., Diabetes Obes Metab 2025):
| Measure | Tirzepatide (pooled doses, n = 124) | Placebo (n = 36) |
|---|---|---|
| Body weight | −21.3% | −5.3% |
| Fat mass | −33.9% | −8.2% |
| Lean mass | −10.9% | −2.6% |
| Share of weight lost that was lean mass | About 25% | About 25% |
Two 2026 reviews put this in context:
- A meta-analysis of 20 randomized trials estimated that lean mass made up 25.4% (95% CI 22.8–28.0) of the weight lost on tirzepatide. The figure for lifestyle interventions alone was 26.2%, and for diet plus resistance training it was 17.5% (Eisa and Barood, Diabetes Obes Metab 2026).
- A systematic review of 35 trials of incretin drugs found a median of 28.3% of weight lost came from muscle-related measures, with wide variation. None of the trials measured objective physical function (Batsis et al., Ann Intern Med 2026).
About “muscle-sparing” claims. Tirzepatide is sometimes promoted as a fat-loss drug that spares muscle because of its GIP action. In the trial data, the share of weight lost as lean mass, about a quarter, matched placebo and diet alone. We found no controlled trials in lean or resistance-trained people, so claims about its effects on “cutting” in that group are untested.
Blood sugar in type 2 diabetes
In SURPASS-1, 478 adults with type 2 diabetes managed by diet and exercise alone received tirzepatide or placebo for 40 weeks. HbA1c (a measure of average blood sugar over about 3 months) started at about 8% (Mounjaro label):
| Arm | HbA1c change | Reached HbA1c under 7% | Weight change |
|---|---|---|---|
| Placebo | −0.1% | 23% | −1.0 kg |
| 5 mg/week | −1.8% | 82% | −6.3 kg |
| 10 mg/week | −1.7% | 85% | −7.0 kg |
| 15 mg/week | −1.7% | 78% | −7.8 kg |
SURPASS-2 compared tirzepatide with semaglutide 1 mg/week in 1,879 patients already on metformin, for 40 weeks (Frías et al., NEJM 2021). HbA1c fell by 2.01, 2.24 and 2.30 percentage points on tirzepatide 5, 10 and 15 mg, compared with 1.86 on semaglutide. All three doses were superior to semaglutide. Weight loss was greater by 1.9, 3.6 and 5.5 kg, respectively. That trial was also open-label, and it used the 1 mg diabetes dose of semaglutide, not the higher doses used for weight loss.
Cardiovascular outcomes
SURPASS-CVOT randomized 13,299 people with type 2 diabetes and established cardiovascular disease to tirzepatide (up to 15 mg) or dulaglutide 1.5 mg. Dulaglutide is a GLP-1 drug already shown to reduce cardiovascular events, so the trial had an active comparator rather than placebo (Nicholls et al., NEJM 2025; Mounjaro label):
| Outcome (median follow-up about 4 years) | Tirzepatide | Dulaglutide | Hazard ratio (95% CI) |
|---|---|---|---|
| Cardiovascular death, heart attack or stroke | 12.2% | 13.1% | 0.92 (0.83–1.01) |
| Death from any cause (label analysis) | 8.5% | 10.1% | 0.84 (0.75–0.94) |
Tirzepatide met the test for being no worse than dulaglutide but did not prove superior on the main outcome. The all-cause death result was not part of the trial’s formal statistical testing, so it is supportive rather than conclusive. FDA added the cardiovascular indication to the Mounjaro label in 2026.
No completed placebo-controlled cardiovascular outcomes trial exists yet in people with obesity and no diabetes. That trial, SURMOUNT-MMO, is still running, with primary completion estimated for October 2027 (Lam et al., Obesity 2025; ClinicalTrials.gov).
Heart failure with preserved ejection fraction
SUMMIT randomized 731 people with heart failure, an ejection fraction of 50% or more, and a BMI of 30 or more to tirzepatide (up to 15 mg) or placebo. Median follow-up was 104 weeks (Packer et al., NEJM 2025):
- Cardiovascular death or worsening heart failure: 9.9% vs 15.3%, HR 0.62 (95% CI 0.41–0.95).
- Worsening heart failure events: 8.0% vs 14.2%, HR 0.54 (95% CI 0.34–0.85).
- Cardiovascular death alone: 2.2% vs 1.4%, HR 1.58 (95% CI 0.52–4.83), too few events to draw conclusions.
- Symptoms and function (KCCQ clinical summary score, 0–100): improved by 6.9 points more than placebo.
Heart failure is not a labeled indication in the current US labels.
Obstructive sleep apnea
SURMOUNT-OSA was two 52-week trials in 469 adults with moderate to severe sleep apnea and obesity: one in people not using positive airway pressure (PAP) machines and one in people using them (Malhotra et al., NEJM 2024; Zepbound label). Severity was measured with the apnea-hypopnea index (AHI), the number of breathing pauses per hour of sleep, which averaged about 50 at baseline:
| Outcome at 52 weeks | Trial 1 (no PAP): tirzepatide vs placebo | Trial 2 (on PAP): tirzepatide vs placebo |
|---|---|---|
| AHI change (events/hour) | −25.3 vs −5.3 | −29.3 vs −5.5 |
| Remission or mild, symptom-free sleep apnea | 42.2% vs 15.9% | 50.2% vs 14.3% |
| Body weight change | −17.7% vs −1.6% | −19.6% vs −2.3% |
Fatty liver disease (MASH)
SYNERGY-NASH was a phase 2 trial in 190 adults with biopsy-proven MASH (metabolic dysfunction-associated steatohepatitis, an inflammatory form of fatty liver disease) and moderate or severe fibrosis (Loomba et al., NEJM 2024). After 52 weeks:
- MASH resolved without worsening fibrosis in 44%, 56% and 62% on 5, 10 and 15 mg, compared with 10% on placebo.
- Fibrosis improved by at least one stage without worsening MASH in 51–55% on tirzepatide, compared with 30% on placebo.
The authors called for larger and longer trials. MASH is not an approved use of tirzepatide in the US.
Side effects and risks
Boxed warning: thyroid C-cell tumors
In a 2-year study in rats, tirzepatide increased thyroid C-cell adenomas and carcinomas at all doses tested, including exposures similar to the maximum human dose. A 6-month study in a transgenic mouse model did not show tumors. Whether this applies to humans is unknown. The labels say:
- tirzepatide is contraindicated in people with a personal or family history of medullary thyroid carcinoma (MTC), or with multiple endocrine neoplasia type 2 (MEN 2);
- routine calcitonin testing or thyroid ultrasound is of uncertain value for early detection.
Gastrointestinal effects
Stomach and bowel effects are the most common reason people stop. In the pooled SURMOUNT-1 and SURMOUNT-2 trials (2,519 people on Zepbound, 958 on placebo) (Zepbound label):
| Adverse reaction | Placebo | 5 mg | 10 mg | 15 mg |
|---|---|---|---|---|
| Nausea | 8% | 25% | 29% | 28% |
| Diarrhea | 8% | 19% | 21% | 23% |
| Vomiting | 2% | 8% | 11% | 13% |
| Constipation | 5% | 17% | 14% | 11% |
| Abdominal pain | 5% | 9% | 9% | 10% |
| Indigestion (dyspepsia) | 4% | 9% | 9% | 10% |
| Injection site reactions | 2% | 6% | 8% | 8% |
| Fatigue | 3% | 5% | 6% | 7% |
| Hair loss | 1% | 5% | 4% | 5% |
| Stopped because of side effects | 3.4% | 4.8% | 6.3% | 6.7% |
Most nausea, vomiting and diarrhea happened during dose increases and eased over time. Severe gastrointestinal reactions occurred in 1.7–3.1% on tirzepatide vs 1% on placebo. Postmarketing reports include ileus (stalled bowel), intestinal obstruction and severe constipation with fecal impaction. Tirzepatide is not recommended for people with severe gastroparesis.
Hair loss was linked to weight loss and was much more common in women (7.1%) than men (0.5%). Acute kidney injury was reported in 0.5% vs 0.2% on placebo. There are postmarketing reports of kidney failure, some requiring dialysis, mostly after dehydration from vomiting or diarrhea.
Pancreas and gallbladder
- Acute pancreatitis: confirmed in 0.2% on tirzepatide and 0.2% on placebo in the weight trials. In the diabetes trials, the rate was 0.23 vs 0.11 patients per 100 patient-years. Fatal hemorrhagic or necrotizing pancreatitis has been reported after approval.
- Pancreatic enzymes: lipase rose by an average of 28–35% and amylase by 20–25%. The meaning of this without symptoms is unknown.
- Gallbladder: gallstones in 1.1% vs 1%, gallbladder inflammation (cholecystitis) in 0.7% vs 0.2%, and gallbladder removal in 0.2% vs none.
Heart rate, blood pressure and blood sugar
- Heart rate rose by an average of 1–3 beats per minute vs no rise on placebo.
- Low blood pressure (hypotension) occurred in 1.6% vs 0.1%, and in 2.2% of those also taking blood pressure medicines.
- Hypoglycemia (glucose under 54 mg/dL) occurred in 4.2% vs 1.3% in people with type 2 diabetes. The rate was 10.3% when combined with a sulfonylurea. It was 0.3% in people without diabetes.
Other label warnings
- Serious allergic reactions, including anaphylaxis and angioedema. Immediate allergic-type reactions occurred in 2.1% vs 0.4% on placebo.
- Diabetic retinopathy may temporarily worsen with rapid blood sugar improvement. People with existing retinopathy should be monitored.
- Pulmonary aspiration during general anesthesia or deep sedation, because food can remain in the stomach. Patients should tell their care team before procedures.
- KwikPen sharing can spread blood-borne infections, even with a new needle.
Mood and suicidal thoughts
Zepbound originally carried a warning about suicidal behavior and ideation, inherited from older weight-loss drugs. In January 2026, after a comprehensive review, FDA found no increased risk with GLP-1 receptor agonist medicines and asked for the warning to be removed from Zepbound, Wegovy and Saxenda (FDA Drug Safety Communication, 2026). The current Zepbound label lists it as removed.
Interactions
- Birth control pills. This interaction is specific to tirzepatide’s labels. After a single 5 mg dose, peak levels of ethinyl estradiol fell by 59% and overall exposure by 20%. The labels advise switching to a non-oral method, or adding a barrier method, for 4 weeks after starting and for 4 weeks after each dose increase.
- Other oral medicines. Slower stomach emptying can change absorption. After the first 5 mg dose, peak acetaminophen levels fell by 50–55%, with no meaningful effect by weeks 4–6. Drugs with a narrow therapeutic range, such as warfarin, need monitoring.
- Insulin and sulfonylureas. These raise the risk of hypoglycemia, and their doses may need to be lowered.
- GLP-1 drugs. Combining tirzepatide with any GLP-1 receptor agonist, such as semaglutide or liraglutide, is not recommended.
Who should not use it
- People with a personal or family history of MTC, or with MEN 2.
- People who have had a serious allergic reaction to tirzepatide or its ingredients.
- Pregnancy. Animal studies showed fetal harm, and human data are insufficient. The Zepbound label says weight loss offers no benefit in pregnancy and to stop the drug once pregnancy is recognized.
- Children, for weight loss. Zepbound’s safety and effectiveness have not been established in children. Mounjaro is approved only for type 2 diabetes in children 10 and older.
Compounded, counterfeit and “research” tirzepatide
Tirzepatide injection was on FDA’s drug shortage list from 2022. FDA declared the shortage resolved on October 2, 2024, and after a court-ordered re-evaluation confirmed this on December 19, 2024. The grace periods for compounding copies ended in 2025. As of April 2026, FDA states that tirzepatide is on neither the drug shortage list nor the outsourcing-facility bulks list (FDA compounding statement).
FDA lists several problems with unapproved tirzepatide (FDA, unapproved GLP-1 drugs):
- Doses beyond the label. FDA has received adverse event reports linked to compounded tirzepatide prescribed at higher doses, more often, or with faster dose increases than the approved label.
- Fake pharmacy labels. Fraudulent compounded tirzepatide has carried the names of pharmacies that do not exist or did not make the product.
- “For research purposes” products. FDA has warned companies selling tirzepatide, retatrutide and other incretin drugs labeled “not for human consumption” directly to consumers with dosing instructions.
- Multi-dose vials. FDA recommends discarding a vial 28 days after first use because of contamination risk.
- Adverse event reports. As of May 31, 2026, FDA had received more than 730 adverse event reports linked to compounded tirzepatide. It notes these are likely underreported.
In sport, tirzepatide is not on the WADA Prohibited List. WADA has placed markers of semaglutide and tirzepatide on its 2026 Monitoring Program, which tracks substances for possible misuse in and out of competition (WADA 2026 Monitoring Program).
Key takeaways
- One molecule, two hormone receptors. Tirzepatide activates both GIP and GLP-1 receptors. A fatty chain binds it to albumin, giving a half-life of about 5 days and once-weekly dosing.
- Very large weight loss in trials. Average loss was about 21% at 15 mg/week over 72 weeks in adults with obesity, compared with 3% on placebo. In an open-label head-to-head trial it beat semaglutide, 20.2% vs 13.7%.
- Weight returns after stopping. In SURMOUNT-4, people switched to placebo regained 14% of their body weight within a year, while those who continued kept losing.
- Lean mass is part of the loss. About a quarter of the weight lost was lean mass, the same share as with placebo or diet alone. There are no trials in lean or trained people.
- Benefits beyond weight. It lowered the risk of progressing to diabetes by more than 90% over 3 years in people with prediabetes, improved sleep apnea, and reduced heart-failure events in SUMMIT. It was no worse than dulaglutide for heart attacks and strokes.
- Stomach side effects dominate. Nausea affected up to 29% of people. Gallbladder disease, pancreatitis, reduced birth-control-pill absorption and a rodent thyroid-tumor boxed warning are the main label risks.
Sources
- Eli Lilly and Company. Mounjaro (tirzepatide) injection, prescribing information. DailyMed; Drugs@FDA, NDA 215866.
- Eli Lilly and Company. Zepbound (tirzepatide) injection, prescribing information. DailyMed; Drugs@FDA, NDA 217806.
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- Food and Drug Administration. FDA approves first medication for obstructive sleep apnea. News release, December 20, 2024. FDA.
- Coskun T, Sloop KW, Loghin C, et al. LY3298176, a novel dual GIP and GLP-1 receptor agonist for the treatment of type 2 diabetes mellitus: from discovery to clinical proof of concept. Mol Metab. 2018;18:3–14. PubMed.
- Jastreboff AM, Aronne LJ, Ahmad NN, et al. Tirzepatide once weekly for the treatment of obesity. N Engl J Med. 2022;387(3):205–216. PubMed.
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- Frías JP, Davies MJ, Rosenstock J, et al. Tirzepatide versus semaglutide once weekly in patients with type 2 diabetes. N Engl J Med. 2021;385(6):503–515. PubMed.
- Nicholls SJ, Pavo I, Bhatt DL, et al. Cardiovascular outcomes with tirzepatide versus dulaglutide in type 2 diabetes. N Engl J Med. 2025;393(24):2409–2420. PubMed.
- Lam CSP, Rodriguez A, Aminian A, et al. Tirzepatide for reduction of morbidity and mortality in adults with obesity: rationale and design of the SURMOUNT-MMO trial. Obesity (Silver Spring). 2025;33(9):1645–1656. PubMed; ClinicalTrials.gov NCT05556512.
- Packer M, Zile MR, Kramer CM, et al. Tirzepatide for heart failure with preserved ejection fraction and obesity. N Engl J Med. 2025;392(5):427–437. PubMed.
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- Loomba R, Hartman ML, Lawitz EJ, et al. Tirzepatide for metabolic dysfunction-associated steatohepatitis with liver fibrosis. N Engl J Med. 2024;391(4):299–310. PubMed.
- Food and Drug Administration. FDA requests removal of suicidal behavior and ideation warning from glucagon-like peptide-1 receptor agonist (GLP-1 RA) medications. Drug Safety Communication, January 13, 2026. FDA.
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- World Anti-Doping Agency. The 2026 Monitoring Program. WADA.