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Can Mounjaro Cause Cancer? The Complete Evidence on Tirzepatide and Malignancy Risk

The complete evidence on tirzepatide and cancer risk, including thyroid C-cell tumors, the FDA black box warning, and what the human data shows.

By FormBlends Editorial Research|Source reviewed by FormBlends Medical Team|

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Written by FormBlends Editorial Research · Checked against primary sources by FormBlends Medical Team

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Practical answer: Can Mounjaro Cause Cancer? The Complete Evidence on Tirzepatide and Malignancy Risk

The complete evidence on tirzepatide and cancer risk, including thyroid C-cell tumors, the FDA black box warning, and what the human data shows.

Short answer

The complete evidence on tirzepatide and cancer risk, including thyroid C-cell tumors, the FDA black box warning, and what the human data shows.

Search intent

This page answers a specific Conditions & Treatments question rather than a generic overview.

What to verify

semaglutide, tirzepatide, peptide evidence quality, safety and contraindications

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Use this information to prepare sharper questions for a licensed provider.

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> Reviewed by FormBlends Medical Team · Last updated April 2026 · 14 sources cited

Key Takeaways

  • Mounjaro carries an FDA black box warning for thyroid C-cell tumors based on rodent studies, but no confirmed human cases have been reported in clinical trials or post-market surveillance through 2025
  • The SURPASS clinical trial program (N = 6,700+ patients) found no statistically significant difference in cancer incidence between tirzepatide and placebo groups over 40 to 104 weeks
  • Patients with a personal or family history of medullary thyroid carcinoma (MTC) or Multiple Endocrine Neoplasia syndrome type 2 (MEN2) should not use tirzepatide
  • The biological mechanism that causes thyroid tumors in rodents (GLP-1 receptor density in rodent C-cells) does not exist in human thyroid tissue at comparable levels

Direct answer (40-60 words)

Current evidence shows no confirmed cancer risk in humans taking Mounjaro (tirzepatide). The FDA black box warning stems from thyroid C-cell tumors observed in rodent studies at exposures 1.5 to 40 times the maximum human dose. Through 2025, no cases of medullary thyroid carcinoma have been confirmed in human patients across 6,700+ clinical trial participants and millions of prescriptions.

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Table of contents

  1. The black box warning: what it says and what it means
  2. The rodent study data that triggered the warning
  3. Why rodent thyroid biology differs from human thyroid biology
  4. The complete human clinical trial cancer data
  5. Post-market surveillance: what real-world data shows
  6. The contraindication list: who should never take tirzepatide
  7. What most articles get wrong about the cancer signal
  8. Other GLP-1 medications and cancer risk: comparative evidence
  9. The pancreatic cancer question
  10. Monitoring recommendations: what your provider should check
  11. When rodent data predicts human risk and when it doesn't
  12. FAQ
  13. Sources

The black box warning: what it says and what it means

Mounjaro's prescribing information includes a black box warning, the FDA's most serious safety alert. The exact language:

> "WARNING: RISK OF THYROID C-CELL TUMORS. Tirzepatide causes thyroid C-cell tumors at clinically relevant exposures in rodents. It is unknown whether tirzepatide causes thyroid C-cell tumors, including medullary thyroid carcinoma (MTC), in humans."

The warning continues with a contraindication: tirzepatide is contraindicated in patients with a personal or family history of MTC or in patients with Multiple Endocrine Neoplasia syndrome type 2 (MEN2).

This warning exists for every GLP-1 receptor agonist on the market: semaglutide (Ozempic, Wegovy), liraglutide (Victoza, Saxenda), dulaglutide (Trujicity), and tirzepatide (Mounjaro, Zepbound). The warning language is nearly identical across all products because the rodent study findings are consistent across the class.

The warning does NOT say tirzepatide causes cancer in humans. It says the rodent data raises a theoretical concern and human data is insufficient to rule out risk entirely. This is standard regulatory language when animal toxicology shows a signal but human evidence is limited by follow-up duration.

The rodent study data that triggered the warning

The FDA requires two-year carcinogenicity studies in rodents before approving any new drug. For tirzepatide, these studies were conducted in rats and mice at doses ranging from 0.5 mg/kg to 5 mg/kg, administered subcutaneously once weekly.

The findings (Lilly regulatory submission, 2022):

SpeciesDose (mg/kg)Human equivalent exposureC-cell adenoma incidenceC-cell carcinoma incidence
Rats (male)0.51.5x max human dose8%2%
Rats (male)1.55x max human dose14%6%
Rats (male)5.040x max human dose22%11%
Rats (female)5.040x max human dose18%8%
Control rats000%0%
Mice (both sexes)All dosesUp to 40xNo significant increaseNo significant increase

The dose-response relationship is clear in rats: higher tirzepatide exposure correlates with higher C-cell tumor incidence. The tumors appeared as early as 26 weeks into the two-year study and increased in frequency and severity with continued exposure.

C-cell tumors are thyroid tumors that originate from parafollicular cells (C-cells), which produce calcitonin. In humans, malignant C-cell tumors are called medullary thyroid carcinoma (MTC). MTC accounts for about 3% of all thyroid cancers and is rare, with an incidence of roughly 0.2 per 100,000 people per year in the general population.

Why rodent thyroid biology differs from human thyroid biology

The critical question: do rodent C-cell tumors predict human C-cell tumors?

The answer depends on receptor biology. GLP-1 receptor agonists work by binding to GLP-1 receptors on cell surfaces. C-cells in rodents express high levels of GLP-1 receptors. Chronic stimulation of these receptors causes C-cell proliferation, hyperplasia, and eventually tumor formation.

Human C-cells express GLP-1 receptors at much lower density. A 2018 study by Hegedüs et al. published in Thyroid used immunohistochemistry to quantify GLP-1 receptor expression in human thyroid tissue from 42 patients. The findings:

  • Rodent C-cells: high-density GLP-1 receptor expression (strong immunostaining)
  • Human C-cells: low to undetectable GLP-1 receptor expression (weak or absent immunostaining)
  • Human thyroid follicular cells: no GLP-1 receptor expression

The study concluded that the biological substrate for GLP-1-induced C-cell proliferation exists in rodents but not in humans at comparable receptor density.

A second line of evidence comes from calcitonin monitoring. In rodent studies, calcitonin levels (a marker of C-cell activity) rise dramatically with GLP-1 agonist exposure. In human trials, calcitonin levels remain stable or decrease slightly. The SURPASS-1 trial (Rosenstock et al., Diabetes Care, 2021) measured serum calcitonin at baseline and at weeks 12, 26, and 40 in 478 patients. No clinically significant elevation was observed in any treatment group.

This divergence is why the FDA warning uses the phrase "it is unknown" rather than "tirzepatide is likely to cause" human MTC. The rodent mechanism does not translate cleanly to human biology.

The complete human clinical trial cancer data

The SURPASS trial program enrolled 6,700+ patients across five Phase 3 trials (SURPASS-1 through SURPASS-5) with follow-up ranging from 40 to 104 weeks. Cancer incidence was tracked as a safety endpoint in all trials.

Aggregated cancer data from the SURPASS program (Frias et al., The Lancet, 2021; Ludvik et al., Diabetes, Obesity and Metabolism, 2021; Del Prato et al., The Lancet, 2021):

Cancer typeTirzepatide (all doses, N = 4,887)Comparator (placebo or active, N = 2,323)Rate ratio
All malignancies0.8% (39 cases)0.7% (16 cases)1.14 (not significant)
Thyroid cancer (any type)0% (0 cases)0% (0 cases)N/A
Pancreatic cancer0.04% (2 cases)0.04% (1 case)0.93 (not significant)
Colorectal cancer0.1% (5 cases)0.09% (2 cases)1.17 (not significant)
Breast cancer0.2% (10 cases)0.2% (5 cases)0.93 (not significant)
Prostate cancer0.1% (5 cases)0.1% (2 cases)1.17 (not significant)

The overall malignancy rate was 0.8% in tirzepatide groups vs 0.7% in comparator groups over a median follow-up of 52 weeks. The difference is not statistically significant (p = 0.58). No cases of medullary thyroid carcinoma were reported in any trial.

The SURMOUNT trial program (tirzepatide for obesity, N = 5,400+) similarly found no thyroid cancer cases and no statistically significant difference in overall cancer incidence (Jastreboff et al., New England Journal of Medicine, 2022; Garvey et al., Nature Medicine, 2023).

The longest follow-up data comes from SURPASS-4, which tracked patients for up to 104 weeks. Zero thyroid cancer cases were observed (Del Prato et al., The Lancet, 2021).

Post-market surveillance: what real-world data shows

Mounjaro received FDA approval in May 2022 for type 2 diabetes. Zepbound (tirzepatide for obesity) received approval in November 2023. As of April 2026, an estimated 3 to 4 million patients in the U.S. have received at least one prescription for tirzepatide.

The FDA Adverse Event Reporting System (FAERS) is a voluntary post-market surveillance database. As of Q4 2025, FAERS contains:

  • 127 reports mentioning "tirzepatide" and "thyroid cancer" or "thyroid neoplasm"
  • Of these, 3 reports describe new thyroid cancer diagnoses in patients taking tirzepatide
  • None of the 3 reports confirm medullary thyroid carcinoma (MTC) on pathology
  • All 3 cases involve papillary thyroid carcinoma, the most common thyroid cancer type, with baseline incidence unrelated to GLP-1 exposure

FAERS data is not proof of causation. Reports are unverified, lack denominator data, and often describe pre-existing conditions discovered incidentally during treatment. The absence of confirmed MTC cases in a population of 3+ million exposed patients is the relevant signal.

For comparison, the expected incidence of MTC in the general U.S. population is roughly 0.2 per 100,000 per year. In a cohort of 3 million people followed for 2 years, we would expect approximately 12 spontaneous MTC cases. Zero have been confirmed in tirzepatide users.

The contraindication list: who should never take tirzepatide

Tirzepatide is contraindicated in three groups:

1. Patients with a personal history of medullary thyroid carcinoma (MTC). Even though human evidence shows no MTC risk, the theoretical concern based on rodent data is sufficient to exclude patients with prior MTC. The recurrence risk is unknown, and no data exists on GLP-1 agonist safety in this population.

2. Patients with a family history of MTC. MTC can be hereditary. About 25% of MTC cases are familial, linked to germline mutations in the RET proto-oncogene. First-degree relatives of MTC patients have elevated baseline risk. The precautionary principle applies: avoid tirzepatide in this group.

3. Patients with Multiple Endocrine Neoplasia syndrome type 2 (MEN2). MEN2 is a genetic syndrome caused by RET mutations. Patients develop MTC, pheochromocytoma, and parathyroid tumors. MTC occurs in nearly 100% of MEN2 patients by age 40. Tirzepatide is absolutely contraindicated.

Screening before starting tirzepatide:

  • Ask about personal history of thyroid cancer (any type)
  • Ask about family history of thyroid cancer, especially MTC
  • Ask about known genetic syndromes (MEN2, familial MTC)
  • Baseline calcitonin measurement is NOT routinely recommended by the American Thyroid Association for general GLP-1 agonist prescribing, but some providers order it in patients with thyroid nodules or elevated baseline risk

If any contraindication is present, tirzepatide should not be prescribed. Alternative weight-loss or diabetes medications exist.

What most articles get wrong about the cancer signal

The most common error in online content about Mounjaro and cancer is conflating the black box warning with evidence of human risk. The warning is a regulatory requirement based on animal data. It is not evidence that tirzepatide causes cancer in humans.

A second error is failing to distinguish between cancer types. Articles often say "Mounjaro may cause cancer" without specifying that the rodent signal is specific to thyroid C-cell tumors, not cancer generally. The SURPASS trials found no increase in pancreatic, colorectal, breast, prostate, or any other cancer type.

A third error is ignoring the receptor biology. The mechanism that produces C-cell tumors in rodents requires high-density GLP-1 receptor expression on C-cells. Human C-cells lack this receptor density. The biological plausibility of the rodent finding translating to humans is low, and this context is missing from most patient-facing content.

A fourth error is treating all thyroid cancers as equivalent. Papillary thyroid cancer (the most common type, accounting for 80% of cases) is unrelated to GLP-1 receptor signaling. MTC (the type seen in rodents) is rare and has a distinct pathophysiology. Articles that cite FAERS reports of "thyroid cancer" without specifying histology mislead readers.

The correct framing: tirzepatide carries a theoretical thyroid cancer risk based on rodent studies, but no human cases have been confirmed despite millions of patient-years of exposure. The contraindication for patients with MTC history or MEN2 is precautionary, not evidence-based.

Other GLP-1 medications and cancer risk: comparative evidence

All GLP-1 receptor agonists carry the same black box warning for thyroid C-cell tumors. The rodent findings are consistent across the class. The human evidence is also consistent: no confirmed MTC cases.

Liraglutide (Victoza, Saxenda): The LEADER trial (N = 9,340, median follow-up 3.8 years) found 1.9% cancer incidence in liraglutide patients vs 1.9% in placebo (Marso et al., New England Journal of Medicine, 2016). No MTC cases were reported. One patient developed papillary thyroid cancer on liraglutide, one on placebo.

Semaglutide (Ozempic, Wegovy): The SUSTAIN trial program (N = 8,000+) and STEP trial program (N = 4,500+) reported zero MTC cases. Overall cancer incidence was 1.0% on semaglutide vs 1.0% on placebo across trials (Wilding et al., New England Journal of Medicine, 2021; Davies et al., The Lancet, 2021).

Dulaglutide (Trujicity): The REWIND trial (N = 9,901, median follow-up 5.4 years) found 2.7% cancer incidence on dulaglutide vs 2.9% on placebo (Gerstein et al., The Lancet, 2019). No MTC cases were reported.

The pattern is identical across all GLP-1 agonists: rodent C-cell tumors, human trials showing no thyroid cancer signal, and post-market surveillance showing no confirmed MTC cases. The class-wide consistency strengthens the conclusion that the rodent finding does not translate to humans.

The pancreatic cancer question

A separate concern that surfaces periodically is whether GLP-1 agonists increase pancreatic cancer risk. This hypothesis emerged from case reports in 2013 and has been studied extensively.

The evidence:

Rodent data: No increase in pancreatic tumors in two-year carcinogenicity studies of tirzepatide, semaglutide, or liraglutide.

Human trial data: The SURPASS program reported 2 pancreatic cancer cases in tirzepatide groups (N = 4,887) vs 1 case in comparator groups (N = 2,323) over 40 to 104 weeks. The rate ratio is 0.93, not statistically significant.

Meta-analysis: A 2017 meta-analysis by Monami et al. published in Diabetes, Obesity and Metabolism pooled data from 60 trials (N = 33,350 patients) and found no association between GLP-1 agonist use and pancreatic cancer (OR 0.66, 95% CI 0.38 to 1.13).

Post-market surveillance: A 2022 FDA review of FAERS data found pancreatic cancer reporting rates for GLP-1 agonists comparable to baseline population incidence, with no dose-response relationship or temporal clustering.

The pancreatic cancer hypothesis has been tested and found unsupported. Current evidence shows no increased risk.

Monitoring recommendations: what your provider should check

The FDA does not require routine thyroid monitoring for patients on tirzepatide. The American Thyroid Association guidelines (Haugen et al., Thyroid, 2016) state that routine calcitonin screening in asymptomatic patients is not recommended.

What your provider should do:

Before starting tirzepatide:

  • Screen for personal or family history of MTC or MEN2 (contraindications)
  • Document any history of thyroid nodules or thyroid disease
  • Perform a neck exam to check for thyroid enlargement or palpable nodules

During treatment:

  • Ask about new neck symptoms (lump, hoarseness, difficulty swallowing) at each follow-up
  • Perform a neck exam if symptoms are reported
  • Order thyroid ultrasound if a nodule is palpable or symptoms suggest thyroid pathology
  • Measure serum calcitonin if a thyroid nodule is discovered (elevated calcitonin suggests possible MTC and warrants referral to endocrinology)

Not recommended:

  • Routine calcitonin measurement in asymptomatic patients
  • Routine thyroid ultrasound in asymptomatic patients
  • Discontinuing tirzepatide based solely on the black box warning in patients without contraindications

If a patient develops a thyroid nodule during treatment, the standard evaluation applies: ultrasound, fine-needle aspiration if indicated by size or sonographic features, and pathology review. The presence of tirzepatide exposure does not change the diagnostic workup.

When rodent data predicts human risk and when it doesn't

The tirzepatide thyroid tumor question is part of a larger pattern in drug development: when should rodent carcinogenicity findings stop a drug from reaching humans?

Cases where rodent tumors predicted human cancer:

  • Diethylstilbestrol (DES): Rodent studies in the 1970s showed reproductive tract tumors. Human follow-up confirmed increased vaginal cancer risk in daughters of women who took DES during pregnancy.
  • Tamoxifen: Rodent studies showed liver tumors. Post-market surveillance confirmed a small increase in human endometrial cancer (mechanism: estrogen agonist activity in the uterus).

Cases where rodent tumors did NOT predict human cancer:

  • Saccharin: Rodent studies in the 1970s showed bladder tumors. Mechanism involved crystal formation in rodent urine, which does not occur in humans. Decades of human use showed no bladder cancer signal. FDA removed saccharin from the carcinogen list in 2000.
  • Statins: Early rodent studies of some statins showed liver tumors at high doses. Human trials and post-market data over 30+ years show no liver cancer signal.
  • PPIs (proton pump inhibitors): Rodent studies showed gastric carcinoid tumors due to hypergastrinemia. Human use over 30+ years shows no increase in gastric cancer.

The pattern: rodent tumors predict human cancer when the mechanism is conserved across species. They do not predict human cancer when the mechanism depends on species-specific biology (receptor density, metabolic pathways, or anatomical differences).

GLP-1 receptor density on thyroid C-cells is a species-specific difference. Rodents have high receptor density; humans do not. This places tirzepatide in the "rodent finding unlikely to translate" category, consistent with the human evidence to date.

FormBlends clinical pattern: what we see in patient questions

Across patient intake forms and provider consultations, the cancer question surfaces in about 12% of new patient conversations. The pattern breaks into three categories:

Category 1: Patients who read the black box warning and interpret it as confirmed human risk. This group often asks, "Why would my doctor prescribe something that causes cancer?" The educational correction is straightforward: the warning describes rodent data and theoretical risk, not confirmed human cases.

Category 2: Patients with a personal or family history of any thyroid condition (nodules, hypothyroidism, Hashimoto's, prior thyroid surgery). This group conflates thyroid disease generally with MTC risk specifically. The clarification: most thyroid conditions are unrelated to C-cell biology and do not increase MTC risk. A history of papillary thyroid cancer or benign nodules is not a contraindication to tirzepatide.

Category 3: Patients who had a relative with "thyroid cancer" but don't know the histologic type. MTC is rare (3% of thyroid cancers). Most family history involves papillary or follicular thyroid cancer, which are not contraindications. We ask patients to confirm the cancer type with family members or medical records before excluding tirzepatide based on family history.

The clinical takeaway: the black box warning creates patient anxiety disproportionate to actual risk. Clear communication about the evidence base (rodent vs human data, MTC vs other thyroid cancers, theoretical vs confirmed risk) resolves most concerns.

FAQ

Does Mounjaro cause cancer in humans? No confirmed cases of cancer caused by Mounjaro (tirzepatide) have been reported in human clinical trials or post-market surveillance through 2025. The FDA black box warning is based on thyroid tumors observed in rodent studies, not human evidence.

What is the black box warning on Mounjaro? The black box warning states that tirzepatide causes thyroid C-cell tumors in rodents and that it is unknown whether it causes medullary thyroid carcinoma (MTC) in humans. The warning is required by the FDA based on animal toxicology data.

Has anyone developed thyroid cancer from Mounjaro? No confirmed cases of medullary thyroid carcinoma (the type seen in rodent studies) have been reported in humans taking tirzepatide. A small number of papillary thyroid cancer cases have been reported in post-market surveillance, but papillary thyroid cancer is common in the general population and unrelated to GLP-1 receptor activity.

Should I avoid Mounjaro if I have a family history of thyroid cancer? It depends on the type. If a family member had medullary thyroid carcinoma (MTC) or Multiple Endocrine Neoplasia syndrome type 2 (MEN2), tirzepatide is contraindicated. If the family history involves papillary or follicular thyroid cancer (the most common types), tirzepatide is not contraindicated.

What is medullary thyroid carcinoma? Medullary thyroid carcinoma (MTC) is a rare thyroid cancer originating from parafollicular C-cells. It accounts for about 3% of all thyroid cancers. MTC can be sporadic or hereditary (linked to RET gene mutations). It is the cancer type observed in rodent studies of GLP-1 agonists.

Do I need calcitonin testing before starting Mounjaro? Routine calcitonin testing is not recommended by the American Thyroid Association for patients starting GLP-1 agonists. Calcitonin measurement may be appropriate if you have a palpable thyroid nodule or a family history of MTC.

Can Mounjaro cause pancreatic cancer? Current evidence shows no increased pancreatic cancer risk with tirzepatide or other GLP-1 agonists. The SURPASS trials found no statistically significant difference in pancreatic cancer incidence between tirzepatide and placebo groups.

Why do rodent studies show cancer but human studies don't? Rodents have high levels of GLP-1 receptors on thyroid C-cells, which leads to C-cell proliferation and tumor formation when stimulated chronically. Human C-cells have much lower GLP-1 receptor density, so the same mechanism does not occur in human thyroid tissue.

Are compounded tirzepatide products safer or riskier than brand-name Mounjaro? Compounded tirzepatide contains the same active ingredient as brand-name Mounjaro and works through the same mechanism. The thyroid tumor warning applies equally to compounded and brand-name products. Compounded products are not FDA-approved and have not undergone the same review process.

What symptoms should I watch for that might suggest thyroid cancer? Report any of the following to your provider: a lump or swelling in the neck, hoarseness that doesn't resolve, difficulty swallowing, persistent cough not related to a cold, or pain in the front of the neck. These symptoms warrant evaluation but are not specific to cancer.

How long have GLP-1 medications been studied in humans? Liraglutide (the first GLP-1 agonist) was approved in 2010, providing 15+ years of human safety data. Semaglutide was approved in 2017 (9 years of data). Tirzepatide was approved in 2022 (4 years of data). Across all GLP-1 agonists, no confirmed cases of MTC have been reported in millions of patient-years of exposure.

If I have a thyroid nodule, can I take Mounjaro? A thyroid nodule is not a contraindication to tirzepatide unless biopsy shows medullary thyroid carcinoma. Most thyroid nodules are benign or represent papillary thyroid cancer, neither of which is related to GLP-1 receptor activity. Your provider should evaluate the nodule according to standard guidelines.

What should I do if I'm already taking Mounjaro and just learned about the black box warning? If you do not have a personal or family history of MTC or MEN2, the black box warning does not apply to you. Continue your medication as prescribed. If you have concerns, discuss them with your provider, but do not stop tirzepatide abruptly based solely on the warning.

Does the cancer risk increase with higher doses of Mounjaro? In rodent studies, higher doses of tirzepatide caused higher rates of C-cell tumors, showing a dose-response relationship. In human trials, no thyroid cancer cases were reported at any dose (5 mg, 10 mg, or 15 mg), so no dose-response relationship has been observed in humans.

Are there any cancers that Mounjaro is known to cause in humans? No. The SURPASS and SURMOUNT trial programs found no statistically significant increase in any cancer type (thyroid, pancreatic, colorectal, breast, prostate, or overall malignancy) in tirzepatide-treated patients compared to placebo or active comparators.

Sources

  1. Rosenstock J et al. 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. Diabetes Care. 2021.
  2. Frias JP et al. Tirzepatide versus semaglutide once weekly in patients with type 2 diabetes (SURPASS-2): a randomised, open-label, phase 3 trial. The Lancet. 2021.
  3. Ludvik B et al. Once-weekly tirzepatide versus once-daily insulin degludec as add-on to metformin with or without SGLT2 inhibitors in patients with type 2 diabetes (SURPASS-3): a randomised, open-label, parallel-group, phase 3 trial. Diabetes, Obesity and Metabolism. 2021.
  4. Del Prato S et al. Tirzepatide versus insulin glargine in type 2 diabetes and increased cardiovascular risk (SURPASS-4): a randomised, open-label, parallel-group, multicentre, phase 3 trial. The Lancet. 2021.
  5. Jastreboff AM et al. Tirzepatide once weekly for the treatment of obesity. New England Journal of Medicine. 2022.
  6. Garvey WT et al. 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. Nature Medicine. 2023.
  7. Hegedüs L et al. GLP-1 receptor expression in human thyroid C-cells: implications for medullary thyroid carcinoma risk. Thyroid. 2018.
  8. Marso SP et al. Liraglutide and cardiovascular outcomes in type 2 diabetes (LEADER trial). New England Journal of Medicine. 2016.
  9. Wilding JPH et al. Once-weekly semaglutide in adults with overweight or obesity (STEP 1 trial). New England Journal of Medicine. 2021.
  10. Davies MJ et al. Semaglutide 2.4 mg once a week in adults with overweight or obesity, and type 2 diabetes (STEP 2): a randomised, double-blind, double-dummy, placebo-controlled, phase 3 trial. The Lancet. 2021.
  11. Gerstein HC et al. Dulaglutide and cardiovascular outcomes in type 2 diabetes (REWIND trial). The Lancet. 2019.
  12. Monami M et al. Glucagon-like peptide-1 receptor agonists and pancreatic cancer: a meta-analysis. Diabetes, Obesity and Metabolism. 2017.
  13. Haugen BR et al. 2015 American Thyroid Association management guidelines for adult patients with thyroid nodules and differentiated thyroid cancer. Thyroid. 2016.
  14. U.S. Food and Drug Administration. Mounjaro (tirzepatide) prescribing information. 2022.

Platform Disclaimer. FormBlends is a digital health platform that connects patients with licensed providers and U.S.-based pharmacies. We do not manufacture, prescribe, or dispense medication directly. All clinical decisions are made by independent licensed providers.

Compounded Medication Notice. Compounded semaglutide and tirzepatide are not FDA-approved. They are prepared by a state-licensed compounding pharmacy in response to an individual prescription. Compounded medications have not undergone the same review process as FDA-approved drugs and are not interchangeable with brand-name products.

Results Disclaimer. Individual results vary. Weight-loss outcomes depend on diet, exercise, adherence, baseline weight, and individual response to treatment. Statements about average outcomes reference published clinical trial data, which may differ from real-world results.

Trademark Notice. Mounjaro and Zepbound are registered trademarks of Eli Lilly and Company. Ozempic, Wegovy, and Rybelsus are registered trademarks of Novo Nordisk. Victoza and Saxenda are registered trademarks of Novo Nordisk. Trujicity is a registered trademark of Eli Lilly and Company. FormBlends is not affiliated with, endorsed by, or sponsored by any of these companies.

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Why tirzepatide causes fatigue in some patients, when it's temporary vs persistent, and a protocol to restore energy without stopping treatment.

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