FDA Approves Tirzepatide for Chronic Weight Management (2023)

Table of Contents

1. What the FDA Did
2. Who the Approval Covers
3. How the Medicine Works and How It Is Given
4. The Trials Behind the Approval
5. Side Effects the FDA Listed
6. Warnings and Who the Label Raises Concerns For
7. Priority Review and Fast Track: What the Designations Mean
8. What the Approval Does Not Do
9. Dates and Legal Status as of 18 October 2026
10. How the Approval Fits Later FDA Actions
11. Primary Documents
12. Key Research Papers
13. Connections
14. Featured Videos

1. What the FDA Did

The FDA news release of 8 November 2023, “FDA Approves New Medication for Chronic Weight Management,” announced the approval of a tirzepatide injection “for chronic weight management in adults with obesity … or overweight … with at least one weight-related condition.” The document type is a drug approval: the agency’s decision that a medicine may be marketed in the United States for a stated use, announced by press release rather than through a Federal Register rule.

The release states that tirzepatide “is already approved” under a different trade name “to be used along with diet and exercise to help improve blood sugar (glucose) in adults with type 2 diabetes mellitus.” The 2023 approval therefore created a second product with the same active ingredient: the weight-management tirzepatide injection, alongside the existing type 2 diabetes tirzepatide product.

The director of the Division of Diabetes, Lipid Disorders, and Obesity in the FDA’s Center for Drug Evaluation and Research was quoted in the release: “Obesity and overweight are serious conditions that can be associated with some of the leading causes of death such as heart disease, stroke and diabetes. In light of increasing rates of both obesity and overweight in the United States, today’s approval addresses an unmet medical need.”

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2. Who the Approval Covers

The approval uses body mass index (BMI), which the release expresses in kilograms per square meter (kg/m²). It covers two groups of adults:

• Adults with obesity: a BMI of 30 kg/m² or greater.
• Adults with overweight: a BMI of 27 kg/m² or greater, together with at least one weight-related condition. The release gives high blood pressure, type 2 diabetes and high cholesterol as examples.

In both groups the medicine is approved for use “in addition to a reduced calorie diet and increased physical activity.” “Chronic weight management” in the release covers both weight reduction and keeping the weight off (“weight reduction and maintenance”).

The release puts the approval in context with two figures: approximately 70% of American adults have obesity or overweight, and many of those with overweight have a weight-related condition. It adds that losing 5% to 10% of body weight through diet and exercise “has been associated with a reduced risk of cardiovascular disease in adults with obesity or overweight.” The condition itself is described on the site’s Obesity page.

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3. How the Medicine Works and How It Is Given

The FDA describes the mechanism in one sentence: the medicine “activates receptors of hormones secreted from the intestine” — glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) — “to reduce appetite and food intake.” The release refers to “a GLP-1 receptor agonist” as a separate kind of medicine when it lists combinations that are not for use (section 6).

How it is given, as the release states it:

• By injection under the skin, once a week.
• The dose is increased step by step over four to 20 weeks to reach a target of 5 milligrams (mg), 10 mg or 15 mg once weekly.
• The maximum dose is 15 mg once weekly.

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4. The Trials Behind the Approval

According to the release, effectiveness was established in two randomized, double-blind, placebo-controlled trials in adults with obesity, or overweight with at least one weight-related condition. In plain terms: participants were assigned to treatment groups by chance, neither they nor the investigators knew who received the medicine, and the comparison group received inactive placebo injections. All participants also followed a reduced-calorie diet and increased physical activity.

• Size and length: weight reduction was measured after 72 weeks in a total of 2,519 patients who received 5 mg, 10 mg or 15 mg of tirzepatide once weekly, and 958 patients who received once-weekly placebo injections.
• Overall result: in both trials, at all three dose levels, the tirzepatide groups had a statistically significant reduction in body weight compared with placebo, and greater proportions of them reached at least 5% weight reduction.
• The larger trial, in adults without diabetes: average starting weight 231 pounds (105 kg), average BMI 38 kg/m². Those assigned to the highest approved dose, 15 mg weekly, lost on average 18% of their body weight compared with those assigned to placebo.
• The trial in adults with type 2 diabetes: average starting weight 222 pounds (101 kg), average BMI 36 kg/m². At 15 mg weekly, the average loss was 12% of body weight compared with placebo.

The release does not name the trials. Published reports of tirzepatide trials in obesity and type 2 diabetes are listed under Key Research Papers; how the site’s other pages summarise the weight-loss evidence for this drug class is set out on GLP-1 Receptor Agonists — Weight Loss Studies.

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5. Side Effects the FDA Listed

The release lists the following side effects:

• nausea, diarrhea, vomiting and constipation;
• abdominal (stomach) discomfort and pain;
• injection-site reactions;
• fatigue;
• hypersensitivity (allergic) reactions, which the release says are typically fever and rash;
• burping;
• hair loss;
• gastroesophageal reflux disease (GERD), in which stomach contents flow back into the esophagus.

A wider account of reported side effects across this drug class is on GLP-1 Receptor Agonists — Side Effects and Cautions.

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6. Warnings and Who the Label Raises Concerns For

The release reports these safety findings and limits:

• Thyroid tumors in rats. The medicine causes thyroid C-cell tumors in rats. The release states that it is unknown whether it causes such tumors, including medullary thyroid cancer, in humans. According to the FDA it is not for use in people with a personal or family history of medullary thyroid cancer, or in people with Multiple Endocrine Neoplasia syndrome type 2 (MEN 2).
• Conditions not studied. It has not been studied in people with a history of pancreas inflammation (pancreatitis) or severe gastrointestinal disease, including severe gastroparesis, which the release describes as a condition that affects normal movement of the muscles in the stomach.
• Combinations. The FDA states it is not for use in combination with the type 2 diabetes tirzepatide product or with a GLP-1 receptor agonist. The safety and effectiveness of using it with other weight-management medicines “have not been established.”
• Severe allergy. It is not for people with a history of severe allergic reaction to tirzepatide or any of the product’s other ingredients. The FDA’s advice in the release is that patients stop the medicine immediately and seek medical help if a severe allergic reaction is suspected.
• Other label warnings. The product carries warnings for pancreatitis, gallbladder problems, hypoglycemia (blood sugar that is too low), acute kidney injury, diabetic retinopathy (damage to the eye’s retina) in people with type 2 diabetes, and suicidal behavior or thinking.

The release also sets out what the agency asks of patients and clinicians, reported here as the FDA’s own guidance: patients are to discuss symptoms of pancreatitis or gallstones with their health care provider; where the medicine is used with insulin or a medicine that causes insulin secretion, patients are to speak with their provider about possibly lowering the dose of those other medicines to reduce the risk of hypoglycemia; and health care providers are to monitor patients with kidney disease, diabetic retinopathy, and depression or suicidal behaviors or thoughts. Decisions about any prescription medicine belong with a clinician.

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7. Priority Review and Fast Track: What the Designations Mean

The release states that the weight-management tirzepatide injection “received Priority Review and Fast Track designations for this indication.” The FDA’s patient pages explain the two terms:

• Fast Track is “a process designed to facilitate the development, and expedite the review of drugs to treat serious conditions and fill an unmet medical need.” The FDA page says diabetes and depression, among others, are considered serious conditions, and that “filling an unmet medical need” means providing a therapy where none exists or one that may be better than available therapy. A Fast Track drug may receive more frequent meetings and written communication with the FDA, and “Rolling Review,” in which a company can submit completed sections of its application rather than waiting for the whole of it.
• Priority Review means “FDA’s goal is to take action on an application within 6 months (compared to 10 months under standard review).” It is given to drugs that, if approved, would be significant improvements in the safety or effectiveness of treating, diagnosing or preventing serious conditions. The FDA page states that the designation “does not alter the scientific/medical standard for approval or the quality of evidence necessary.”

Both designations concern the speed and process of the review, not a lower bar for approval.

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8. What the Approval Does Not Do

• It does not cover people outside the approved groups. The approval is for adults with a BMI of 30 or more, or 27 or more with at least one weight-related condition. It is not an approval for weight loss in people without obesity or overweight with a weight-related condition.
• It does not replace diet and activity. The approved use is “in addition to” a reduced-calorie diet and increased physical activity, and the trials tested the medicine on top of both.
• It does not establish use with other weight-management medicines. The release says the safety and effectiveness of combining it with other weight-management medicines “have not been established,” and states it is not for use with the type 2 diabetes tirzepatide product or a GLP-1 receptor agonist.
• It is not an approval of any compounded tirzepatide. Compounded copies are a separate matter, reported on the later pages listed in section 10.

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9. Dates and Legal Status as of 18 October 2026

• Approved and announced: 8 November 2023 (FDA news release).
• Review: Priority Review and Fast Track designations for the weight-management indication.
• Earlier approval of the same ingredient: the type 2 diabetes tirzepatide product, already approved before November 2023.

Status as of 18 October 2026: approval in effect. A check of the Federal Register through 18 October 2026 found no FDA document withdrawing, suspending or narrowing the approval. The later FDA documents on tirzepatide concern compounding rather than the approval itself: a notice of 1 May 2026 (91 FR 23431, FR Doc. 2026-08552, Docket No. FDA-2018-N-3240) in which the FDA proposes not to include semaglutide, tirzepatide and liraglutide on the “503B Bulks List” — the list of bulk drug substances (active pharmaceutical ingredients) for which there is a clinical need for outsourcing facilities to use in compounding — and a notice of 26 June 2026 (91 FR 38719, FR Doc. 2026-12937) that extended the comment period on that proposal to 30 July 2026. No final decision on that proposal appeared in the Federal Register by 18 October 2026. It is reported on FDA Proposal on Compounded Semaglutide and Tirzepatide (2026).

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10. How the Approval Fits Later FDA Actions

The 2023 approval was the start of a longer regulatory story for tirzepatide. In the years that followed, the FDA’s actions turned to supply and to compounded copies:

• The tirzepatide shortage of 2022–2024, its end, and the limit this placed on compounded copies are reported on FDA Ends the Tirzepatide Shortage, Limiting Compounded Copies (2024).
• The parallel story for semaglutide, a GLP-1 receptor agonist, is on FDA Ends the Semaglutide Shortage and Compounded Copies (2025).
• The 2026 proposal on bulk compounding of semaglutide, tirzepatide and liraglutide is on FDA Proposal on Compounded Semaglutide and Tirzepatide (2026).
• A related approval in the same field, for a heart-risk indication of semaglutide in people with obesity, is on FDA Approves Semaglutide to Cut Heart Risk in Obesity (2024).

Among the other FDA drug actions of 2023 reported on this site are the full approval of lecanemab for early Alzheimer’s disease, the first over-the-counter naloxone nasal spray and the updated boxed warnings on prescription stimulants.

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11. Primary Documents

1. U.S. Food and Drug Administration (2023). FDA Approves New Medication for Chronic Weight Management. FDA News Release, 8 November 2023 — fda.gov news release
2. U.S. Food and Drug Administration. Fast Track. Patient information page (Fast Track, Breakthrough Therapy, Accelerated Approval, Priority Review) — fda.gov Fast Track page
3. U.S. Food and Drug Administration. Priority Review. Patient information page, content current as of 4 January 2018 — fda.gov Priority Review page
4. Food and Drug Administration, HHS (2026). List of Bulk Drug Substances for Which There Is a Clinical Need Under Section 503B of the Federal Food, Drug, and Cosmetic Act; Notice. Federal Register 91 FR 23431, 1 May 2026. Docket No. FDA-2018-N-3240 — FR Doc. 2026-08552
5. Food and Drug Administration, HHS (2026). List of Bulk Drug Substances for Which There Is a Clinical Need Under Section 503B of the Federal Food, Drug, and Cosmetic Act; Extension of Comment Period. Federal Register 91 FR 38719, 26 June 2026. Docket No. FDA-2018-N-3240 — FR Doc. 2026-12937

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Key Research Papers

1. Jastreboff AM, Aronne LJ, Ahmad NN, Wharton S, Connery L, Alves B, Kiyosue A, Zhang S, Liu B, Bunck MC, Stefanski A; SURMOUNT-1 Investigators (2022). Tirzepatide Once Weekly for the Treatment of Obesity. New England Journal of Medicine 387(3):205-216 — PubMed PMID: 35658024
2. Garvey WT, Frias JP, Jastreboff AM, le Roux CW, Sattar N, Aizenberg D, Mao H, Zhang S, Ahmad NN, Bunck MC, Benabbad I, Zhang XM; SURMOUNT-2 investigators (2023). Tirzepatide once weekly for the treatment of obesity in people with type 2 diabetes (SURMOUNT-2): a double-blind, randomised, multicentre, placebo-controlled, phase 3 trial. Lancet 402(10402):613-626 — PubMed PMID: 37385275
3. Wadden TA, Chao AM, Machineni S, Kushner R, Ard J, Srivastava G, Halpern B, Zhang S, Chen J, Bunck MC, Ahmad NN, Forrester T (2023). Tirzepatide after intensive lifestyle intervention in adults with overweight or obesity: the SURMOUNT-3 phase 3 trial. Nature Medicine 29(11):2909-2918 — PubMed PMID: 37840095
4. Aronne LJ, Sattar N, Horn DB, Bays HE, Wharton S, Lin WY, Ahmad NN, Zhang S, Liao R, Bunck MC, Jouravskaya I, Murphy MA; SURMOUNT-4 Investigators (2024). Continued Treatment With Tirzepatide for Maintenance of Weight Reduction in Adults With Obesity: The SURMOUNT-4 Randomized Clinical Trial. JAMA 331(1):38-48 — PubMed PMID: 38078870
5. Rosenstock J, Wysham C, Frías JP, Kaneko S, Lee CJ, Fernández Landó L, Mao H, Cui X, Karanikas CA, Thieu VT (2021). Efficacy and safety of a novel dual GIP and GLP-1 receptor agonist tirzepatide in patients with type 2 diabetes (SURPASS-1): a double-blind, randomised, phase 3 trial. Lancet 398(10295):143-155 — PubMed PMID: 34186022
6. Frías JP, Davies MJ, Rosenstock J, Pérez Manghi FC, Fernández Landó L, Bergman BK, Liu B, Cui X, Brown K; SURPASS-2 Investigators (2021). Tirzepatide versus Semaglutide Once Weekly in Patients with Type 2 Diabetes. New England Journal of Medicine 385(6):503-515 — PubMed PMID: 34170647

The first four papers are published phase 3 trials of once-weekly tirzepatide in adults with obesity or overweight, with and without type 2 diabetes, including a trial of continued treatment for keeping weight off. The last two are phase 3 trials in type 2 diabetes, the use for which tirzepatide was first approved. The FDA release does not name the trials it relied on.

PubMed Topic Searches

1. PubMed: tirzepatide and obesity
2. PubMed: tirzepatide and weight maintenance
3. PubMed: tirzepatide safety

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Connections

• FDA Actions of 2023
• FDA and Regulation
• GLP-1 Receptor Agonists
• GLP-1 Weight Loss Studies
• GLP-1 Side Effects and Cautions
• Obesity
• Type 2 Diabetes
• Tirzepatide Shortage Ends (2024)
• Semaglutide Heart-Risk Approval (2024)
• Semaglutide Shortage Ends (2025)
• Compounded GLP-1 Proposal (2026)
• Lecanemab Full Approval (2023)
• OTC Naloxone Nasal Spray (2023)
• Stimulant Boxed Warnings (2023)

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