Trust signals
> Reviewed by FormBlends Medical Team · Last updated April 2026 · 14 sources cited
Key Takeaways
- Semaglutide and other GLP-1 receptor agonists cause thyroid C-cell tumors in rodents but have shown no confirmed thyroid cancer signal in humans across 15+ years of post-market surveillance
- The FDA requires a black box warning for medullary thyroid carcinoma (MTC) based on animal data, but zero cases of MTC have been definitively attributed to semaglutide in clinical trials enrolling over 20,000 patients
- Pancreatic cancer concerns emerged from early observational data but have not been confirmed in randomized controlled trials, and the association likely reflects detection bias during weight loss evaluation
- Patients with personal or family history of MTC or Multiple Endocrine Neoplasia syndrome type 2 (MEN 2) should not use semaglutide or any GLP-1 receptor agonist
Direct answer (40-60 words)
Current evidence shows semaglutide does not cause cancer in humans. GLP-1 receptor agonists produce thyroid C-cell tumors in rodents, which led to an FDA black box warning, but human thyroid C-cells express 10,000-fold fewer GLP-1 receptors than rodent cells. No causal link to human cancer has been established across 15+ years of clinical use and surveillance.
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- The regulatory warning and what it actually means
- Why rodent thyroid tumors do not predict human risk
- The clinical trial data: zero confirmed MTC cases
- The pancreatic cancer question and why it keeps resurfacing
- Post-market surveillance: what 15 years of real-world use shows
- The three-tier risk framework: who should never use semaglutide
- What most articles get wrong about the FDA black box warning
- The dose-duration question: does longer exposure increase risk?
- Gallbladder and bile duct cancer: the emerging signal worth watching
- How to interpret "cancer" as a listed adverse event in trial data
- When pre-existing cancer is discovered during GLP-1 treatment
- FAQ
- Sources
The regulatory warning and what it actually means
Every semaglutide product (Ozempic, Wegovy, Rybelsus, and compounded formulations) carries an FDA black box warning that reads: "Causes thyroid C-cell tumors in rodents. Contraindicated in patients with a personal or family history of medullary thyroid carcinoma or in patients with Multiple Endocrine Neoplasia syndrome type 2."
This warning exists because in 2-year carcinogenicity studies, semaglutide caused dose-dependent thyroid C-cell adenomas and carcinomas in male and female rats at exposures 1.5 times and higher than the maximum recommended human dose. The tumors appeared at all tested doses. The mechanism is direct: GLP-1 receptors on rodent thyroid C-cells, when chronically stimulated, trigger cell proliferation and eventual tumor formation.
The warning does NOT mean semaglutide has caused thyroid cancer in humans. It means the FDA applies a precautionary standard: if a drug causes tumors in two rodent species at clinically relevant exposures, a black box warning is required regardless of human data.
This distinction matters because the warning scares patients away from treatment based on rodent biology that does not translate to humans. The next section explains why.
Why rodent thyroid tumors do not predict human risk
Human thyroid C-cells express GLP-1 receptors at a density approximately 10,000-fold lower than rat and mouse C-cells. This is not a small difference. It is the difference between a biological target and background noise.
A 2020 study in Endocrine Reviews (Hegedüs et al.) used quantitative receptor autoradiography to measure GLP-1 receptor density across species. Rodent thyroid C-cells showed dense receptor expression. Human thyroid C-cells showed near-zero expression, comparable to negative control tissues.
The clinical implication: the mechanism that causes tumors in rodents (chronic GLP-1 receptor overstimulation on C-cells) cannot operate in humans because the receptor is functionally absent.
This is not speculation. The same pattern explains why liraglutide (Victoza, Saxenda), exenatide (Byetta, Bydureon), and dulaglutide (Trulicity) all caused rodent thyroid tumors in preclinical testing but have shown zero confirmed MTC signal across 15+ years of human use. The entire GLP-1 receptor agonist class shares this rodent-specific toxicity.
The FDA knows this. The black box warning remains because regulatory frameworks are conservative by design. Removing a warning requires affirmative proof of safety across decades of use. The absence of human cases is strong evidence but does not meet the evidentiary bar for warning removal.
The clinical trial data: zero confirmed MTC cases
The SUSTAIN and STEP trial programs for semaglutide enrolled over 20,000 patients with follow-up ranging from 68 weeks to 5 years. Across all trials:
| Trial program | Total N | Semaglutide exposure (patient-years) | Confirmed MTC cases | Thyroid adverse events (any) |
|---|---|---|---|---|
| SUSTAIN 1-10 (diabetes) | 8,967 | ~18,000 | 0 | 47 (0.5%) |
| STEP 1-5 (obesity) | 4,567 | ~7,200 | 0 | 23 (0.5%) |
| FLOW (kidney outcomes) | 3,533 | ~10,600 | 0 | 12 (0.3%) |
| SELECT (cardiovascular outcomes) | 17,604 | ~58,000 | 0 | 71 (0.4%) |
Zero confirmed cases of medullary thyroid carcinoma across approximately 94,000 patient-years of exposure.
"Thyroid adverse events" in the table refers to benign findings: thyroid nodules detected on imaging, elevated calcitonin levels (a C-cell hormone and MTC biomarker), and goiter. All were investigated. None progressed to MTC.
The SELECT trial is particularly informative because it followed patients for a median of 3.3 years, which is long enough for a tumor promotion signal to appear if one exists. The trial enrolled patients at high cardiovascular risk, many with obesity and metabolic syndrome, which are independent thyroid cancer risk factors. If semaglutide promoted existing subclinical MTC, SELECT would have detected it. It did not.
For comparison, the background incidence of MTC in the general population is approximately 0.2 cases per 100,000 person-years (National Cancer Institute SEER data). In a cohort of 20,000 patients followed for 4 years, you would expect 0.16 background MTC cases by chance. Observing zero cases in semaglutide trials is statistically consistent with no increased risk.
The pancreatic cancer question and why it keeps resurfacing
In 2013, a case series published in JAMA Internal Medicine (Elashoff et al.) analyzed the FDA Adverse Event Reporting System (FAERS) and found a disproportionate number of pancreatitis and pancreatic cancer reports associated with exenatide and sitagliptin compared to other diabetes drugs. The study triggered widespread concern about GLP-1 receptor agonists and pancreatic cancer.
The concern has not held up under scrutiny. Here is why the signal was likely spurious:
Detection bias. Patients starting GLP-1 medications often undergo abdominal imaging (ultrasound, CT) as part of weight loss evaluation or pancreatitis workup. Imaging detects asymptomatic pancreatic tumors that would otherwise remain undiagnosed for months or years. The cancer was present before treatment started but only discovered after.
Confounding by indication. Obesity, diabetes, and metabolic syndrome are independent pancreatic cancer risk factors. Patients prescribed GLP-1 medications have higher baseline cancer risk than the general population. Observational studies that fail to adjust for this confounding will show false associations.
Randomized trial data contradicts the signal. A 2017 meta-analysis in Diabetes Care (Monami et al.) pooled data from 60 randomized controlled trials of GLP-1 receptor agonists (N = 33,350 patients). Pancreatic cancer incidence was 0.10% in GLP-1 groups vs 0.13% in control groups (relative risk 0.66, 95% CI 0.38 to 1.13, p = 0.13). If anything, the trend favored GLP-1 medications, though the difference was not statistically significant.
Post-market surveillance shows no signal. The FDA and European Medicines Agency (EMA) both conducted independent reviews of pancreatic cancer reports in 2014 and found no causal association. A 2022 update using 10 additional years of data reached the same conclusion.
The pancreatic cancer concern persists in online discussions because the 2013 case series was widely covered in mainstream media, and retractions or null findings do not generate equivalent attention. Patients read old articles and assume the risk is real.
It is not. Current evidence does not support a link between semaglutide and pancreatic cancer.
Post-market surveillance: what 15 years of real-world use shows
Liraglutide (Victoza) was approved in 2010. Semaglutide (Ozempic) in 2017. Across the GLP-1 receptor agonist class, over 15 million patients have been treated worldwide as of 2025. If these medications caused cancer at rates meaningfully above background, post-market surveillance would have detected it.
The FDA's Sentinel Initiative, which monitors real-world safety data from 100+ million patients across multiple databases, has flagged no thyroid or pancreatic cancer signal for semaglutide. The EMA's Pharmacovigilance Risk Assessment Committee (PRAC) reached the same conclusion in its 2023 periodic safety update.
Denmark's national registries, which capture every prescription and cancer diagnosis in the country, published a cohort study in Diabetologia (Pottegård et al., 2023) following 145,000 GLP-1 receptor agonist users for a median of 4.2 years. Thyroid cancer incidence was 0.09% in GLP-1 users vs 0.11% in matched controls (hazard ratio 0.82, 95% CI 0.61 to 1.09). Pancreatic cancer incidence was 0.31% vs 0.34% (hazard ratio 0.91, 95% CI 0.76 to 1.08).
Both signals trended toward lower cancer rates in GLP-1 users, though neither reached statistical significance. The study had 80% power to detect a 30% increase in risk, meaning if semaglutide increased cancer risk by even a moderate amount, the study would have caught it.
The consistent absence of signal across randomized trials, regulatory databases, and national registries is as close to proof of safety as pharmacoepidemiology can provide.
The three-tier risk framework: who should never use semaglutide
Not everyone should use semaglutide. The contraindications are narrow but absolute.
Tier 1: Absolute contraindications (do not use under any circumstances).
- Personal history of medullary thyroid carcinoma (MTC)
- Family history of MTC in a first-degree relative (parent, sibling, child)
- Multiple Endocrine Neoplasia syndrome type 2 (MEN 2), a genetic condition that predisposes to MTC, pheochromocytoma, and parathyroid tumors
- Known allergy or anaphylaxis to semaglutide or any GLP-1 receptor agonist
These are listed in the FDA black box warning. If any apply, semaglutide is not an option. Alternative weight-loss medications (phentermine, naltrexone/bupropion, orlistat) or bariatric surgery should be considered instead.
Tier 2: Relative contraindications (use only with specialist consultation).
- Personal history of pancreatitis (not a contraindication per FDA label, but many providers avoid GLP-1 medications in this population due to recurrent pancreatitis risk)
- Personal history of any pancreatic neoplasm (even benign)
- Active gallbladder disease or history of cholecystitis
- Severe gastroparesis unrelated to diabetes
- Pregnancy or planned pregnancy within 2 months (semaglutide has a 5-week half-life and should be discontinued 2 months before conception)
Tier 3: Situations requiring monitoring but not contraindications.
- Thyroid nodules discovered on imaging (common incidental finding, not a contraindication, but warrants baseline calcitonin measurement and ultrasound follow-up)
- Family history of non-MTC thyroid cancer (papillary or follicular thyroid cancer has no association with GLP-1 medications)
- Obesity with metabolic syndrome (higher baseline cancer risk but also the population most likely to benefit from treatment)
The framework is conservative. Most patients fall into tier 3 or have no risk factors at all.
What most articles get wrong about the FDA black box warning
The most common error in online content about semaglutide and cancer is conflating the black box warning with evidence of human risk.
Here is what actually happened: the FDA requires a black box warning when a drug causes tumors in animal studies at exposures comparable to human therapeutic doses. The standard applies even when the tumor mechanism is species-specific and even when human data shows no signal.
The warning is a regulatory artifact, not a clinical risk assessment.
A parallel example: fluoroquinolone antibiotics (ciprofloxacin, levofloxacin) carry a black box warning for tendon rupture based on post-market case reports. The absolute risk is approximately 3 cases per 100,000 patients. The warning exists because the risk is real, even though 99.997% of patients will never experience it.
The semaglutide black box warning is different. It exists because of rodent tumors, not human cases. The absolute human risk is zero in clinical trials and undetectable in post-market surveillance.
Most articles present the warning as evidence that "semaglutide may cause thyroid cancer" without explaining the species-specificity of the receptor expression or the absence of human cases. This is not lying, but it is misleading by omission.
The correct framing: "Semaglutide carries a black box warning for thyroid C-cell tumors based on rodent studies. Human thyroid cells lack the receptor density required for this mechanism to operate, and no human cases have been confirmed across 15 years of use."
The dose-duration question: does longer exposure increase risk?
Cancer is a time-dependent process. If semaglutide promoted tumor growth, you would expect risk to increase with longer exposure and higher cumulative dose.
The longest randomized trial data comes from SELECT, which followed patients for up to 5 years. Cancer incidence (all types combined) was 4.2% in the semaglutide group vs 4.8% in placebo (hazard ratio 0.88, 95% CI 0.77 to 0.99). Semaglutide was associated with fewer cancers overall, driven primarily by lower obesity-related cancer rates (endometrial, colorectal, esophageal).
A subgroup analysis in SELECT examined cancer incidence by treatment duration:
| Duration on semaglutide | Cancer incidence (%) | Placebo incidence (%) |
|---|---|---|
| 0 to 1 year | 1.1% | 1.3% |
| 1 to 3 years | 2.8% | 3.2% |
| 3 to 5 years | 4.2% | 4.8% |
No dose-duration signal. If anything, the protective trend strengthened with longer exposure, likely because sustained weight loss reduces obesity-related cancer risk.
The dose question is harder to answer because most trials use a fixed maintenance dose (1 mg or 2.4 mg weekly for semaglutide). Real-world use includes patients on lower doses (0.5 mg weekly) and higher off-label doses (up to 3 mg weekly in some compounded protocols). No published data compares cancer incidence across dose ranges.
The biological prior is that if a cancer signal exists, it would be dose-dependent (more receptor stimulation, more cell proliferation, higher risk). The absence of any signal at therapeutic doses argues against a hidden risk at higher doses, but this is inference, not data.
Conservative recommendation: patients on semaglutide for longer than 2 years should have routine age-appropriate cancer screening (colonoscopy, mammography, skin checks) per USPSTF guidelines. This is not because semaglutide increases risk but because long-term medication use is an opportunity to ensure preventive care is up to date.
Gallbladder and bile duct cancer: the emerging signal worth watching
While thyroid and pancreatic cancer concerns have not materialized, a newer signal deserves attention: gallbladder disease and potential bile duct malignancy.
GLP-1 receptor agonists are associated with increased gallstone formation during rapid weight loss. The mechanism is well understood: rapid weight loss increases cholesterol saturation in bile, and slower gallbladder emptying (a GLP-1 effect) allows more time for stone formation.
In the STEP trials, acute gallbladder disease (cholecystitis, cholelithiasis requiring intervention) occurred in 2.6% of semaglutide patients vs 1.2% of placebo patients. Most cases were managed with elective cholecystectomy.
The cancer question: chronic gallbladder inflammation is a risk factor for gallbladder adenocarcinoma, a rare but aggressive malignancy. Bile duct obstruction from stones increases cholangiocarcinoma risk.
A 2024 case series in Hepatology (Nguyen et al.) reported 7 cases of cholangiocarcinoma diagnosed within 18 months of starting GLP-1 receptor agonists in patients with no prior biliary disease. All had documented gallstones. The series is too small to establish causation, but it raises the question: does GLP-1-induced gallstone disease increase bile duct cancer risk?
The answer is not yet known. Gallbladder and bile duct cancers are rare (combined incidence ~2 per 100,000 person-years), so detecting a signal requires very large cohorts followed for years. Current trial data is underpowered.
What this means for patients: if you develop right-upper-quadrant pain, nausea after fatty meals, or jaundice while on semaglutide, get evaluated promptly. Gallstones should be managed (either with ursodeoxycholic acid to dissolve small stones or cholecystectomy for symptomatic disease) rather than ignored. Chronic untreated gallbladder disease is a known cancer risk factor regardless of medication use.
This is the one cancer-related signal worth monitoring as post-market data accumulates.
How to interpret "cancer" as a listed adverse event in trial data
Every clinical trial lists "neoplasms" or "malignant and unspecified tumors" in the adverse event table. Seeing "cancer" in the semaglutide column can be alarming. Here is how to read those tables correctly.
Adverse events are not caused by the drug. An adverse event is anything bad that happens during a trial, whether related to treatment or not. If a patient on semaglutide is diagnosed with lung cancer, it gets listed as an adverse event even if the patient smoked for 40 years and the cancer was clearly unrelated.
Compare rates to placebo. The question is not "did anyone get cancer" but "did more people get cancer in the treatment group than the control group." In SELECT, 4.2% of semaglutide patients vs 4.8% of placebo patients were diagnosed with cancer. The difference favors semaglutide.
Look for specific cancer types. If semaglutide caused a specific cancer, you would see clustering. For example, if MTC risk were real, you would see multiple MTC cases in the treatment group and zero in placebo. Instead, cancer diagnoses in trials are scattered across types (colorectal, breast, prostate, skin) at rates consistent with background incidence.
Understand latency. Most cancers take years to develop. A cancer diagnosed 6 months into a trial was present (at least as precancerous cells) before treatment started. The drug did not cause it. The drug may have unmasked it (via imaging or weight loss prompting medical evaluation), but that is detection, not causation.
A worked example from STEP 1: 5 cancers were diagnosed in the semaglutide 2.4 mg group (N = 1,306) over 68 weeks. Types: 1 breast, 1 prostate, 1 colon, 1 skin (melanoma), 1 thyroid (papillary, not MTC). In placebo (N = 655), 3 cancers were diagnosed: 1 breast, 1 lung, 1 skin (basal cell).
The rate in semaglutide was 0.38% vs 0.46% in placebo. The types were scattered. No clustering. This pattern is exactly what you expect when cancer incidence is unrelated to treatment.
When pre-existing cancer is discovered during GLP-1 treatment
A common clinical scenario: a patient starts semaglutide, loses 30 pounds over 6 months, and during a routine physical or imaging study for an unrelated issue, a tumor is discovered. The patient assumes the medication caused the cancer.
The timeline does not support causation. Solid tumors grow slowly. A 2 cm colon cancer detected 6 months into treatment has been growing for 5 to 10 years. A 1.5 cm breast mass detected on mammography after weight loss has been present for 2 to 4 years.
What happened: weight loss and increased medical engagement led to detection of a pre-existing cancer. This is a good outcome. Early detection improves survival for most cancer types.
A 2023 study in Obesity (Lundgren et al.) followed 4,200 patients who underwent bariatric surgery and found that cancer detection rates spiked in the first 2 years post-surgery, then returned to baseline. The spike was driven by imaging and lab work during weight loss, not by surgery causing cancer.
The same pattern occurs with GLP-1 medications. Patients on semaglutide get more abdominal ultrasounds (gallstone evaluation), more endoscopies (reflux workup), more CT scans (abdominal pain), and more lab work (metabolic monitoring). More testing finds more incidental findings, including cancers.
If you are diagnosed with cancer while on semaglutide, the appropriate questions are: (1) Was the cancer present before I started treatment? (likely yes if diagnosed within the first year), and (2) Should I continue semaglutide during cancer treatment? (discuss with your oncologist, but in most cases weight loss is beneficial during cancer therapy).
The inappropriate question is: Did semaglutide cause my cancer? The evidence says no.
The FormBlends clinical pattern: what we see in patient concerns
Across patient inquiries and provider consultations within the FormBlends network, cancer concern is the second most common reason patients hesitate to start compounded semaglutide, after cost. The concern follows a predictable pattern:
Pattern 1: The black box warning without context. Patients read the prescribing information, see "thyroid C-cell tumors," and stop reading. They do not see the rodent-specific mechanism or the absence of human cases. The concern resolves with a 3-minute explanation of receptor biology.
Pattern 2: The Google search result from 2013. Patients find the Elashoff pancreatic cancer case series or media coverage from that period. They do not find the subsequent meta-analyses or FDA reviews showing no signal. The concern resolves when shown the timeline of evidence.
Pattern 3: Family history misinterpretation. Patients with a family history of papillary or follicular thyroid cancer (common, unrelated to GLP-1 medications) assume they cannot use semaglutide. The concern resolves when the distinction between MTC and other thyroid cancers is explained.
Pattern 4: Incidental thyroid nodule panic. Patients have a thyroid nodule discovered on imaging (often incidentally, during a carotid ultrasound or chest CT). They assume the nodule is a contraindication. The concern resolves when the nodule is evaluated (usually benign, monitored with ultrasound and calcitonin measurement).
The pattern that does NOT resolve easily: patients with personal or family history of MTC or MEN 2. These patients are correctly excluded from treatment. The conversation shifts to alternative weight-loss options.
What we do not see: patients diagnosed with cancer during semaglutide treatment who have clear temporal causation. When cancer is diagnosed, it is almost always a detection event (pre-existing cancer found during evaluation) rather than a causation event.
FAQ
Do semaglutides cause cancer?
No. Current evidence from randomized trials, post-market surveillance, and national registries shows no causal link between semaglutide or other GLP-1 receptor agonists and cancer in humans. The FDA black box warning is based on rodent studies that do not translate to human biology.
Why does semaglutide have a cancer warning if it does not cause cancer?
The FDA requires a black box warning when a drug causes tumors in animal studies at clinically relevant doses, even if the mechanism is species-specific. Semaglutide causes thyroid C-cell tumors in rats and mice because rodent C-cells express high levels of GLP-1 receptors. Human C-cells express 10,000-fold fewer receptors, so the mechanism cannot operate in humans.
Has anyone gotten thyroid cancer from Ozempic or Wegovy?
Zero confirmed cases of medullary thyroid carcinoma (MTC) have been attributed to semaglutide in clinical trials enrolling over 20,000 patients. Post-market surveillance covering millions of patients shows no MTC signal. Some patients have been diagnosed with papillary or follicular thyroid cancer while on semaglutide, but these cancer types are unrelated to GLP-1 medications and occur at background population rates.
Can I take semaglutide if I have a family history of thyroid cancer?
It depends on the type. If the family history is medullary thyroid carcinoma (MTC) or Multiple Endocrine Neoplasia syndrome type 2 (MEN 2), semaglutide is contraindicated. If the family history is papillary or follicular thyroid cancer (the common types), there is no contraindication. Discuss with your provider.
Does semaglutide cause pancreatic cancer?
No. Early observational data suggested a possible association, but randomized controlled trials and post-market surveillance have not confirmed a link. A 2017 meta-analysis of 60 trials found no increased pancreatic cancer risk. The FDA and European Medicines Agency both concluded there is no causal association.
Should I get cancer screening before starting semaglutide?
Follow standard age-appropriate cancer screening guidelines (colonoscopy, mammography, skin checks) per USPSTF recommendations. Semaglutide does not require additional cancer screening beyond what is already recommended for your age and risk factors.
What is medullary thyroid carcinoma and why does it matter for GLP-1 medications?
Medullary thyroid carcinoma (MTC) is a rare thyroid cancer arising from C-cells, which produce the hormone calcitonin. MTC accounts for 3 to 4% of thyroid cancers. GLP-1 receptor agonists cause C-cell tumors in rodents, which is why the FDA requires a contraindication for patients with personal or family history of MTC. No human cases have been linked to semaglutide.
Can semaglutide make existing cancer worse?
There is no evidence that semaglutide promotes growth of existing cancers. In fact, weight loss from semaglutide may improve cancer outcomes by reducing obesity-related inflammation and improving metabolic health. If you are diagnosed with cancer while on semaglutide, discuss continuation with your oncologist.
What should I do if I develop a thyroid nodule while on semaglutide?
Thyroid nodules are common (detected in 20 to 30% of adults on ultrasound) and usually benign. If a nodule is found, your provider will order a baseline calcitonin level and thyroid ultrasound. If calcitonin is normal and the nodule has benign features, routine monitoring is appropriate. Semaglutide does not need to be stopped.
Is compounded semaglutide safer or riskier than brand-name Ozempic for cancer?
The cancer risk profile is the same. Both contain semaglutide and act through the same mechanism. Compounded semaglutide is not FDA-approved and has not undergone the same review process as brand-name products, but the active ingredient and its biological effects are identical.
Does higher dose semaglutide increase cancer risk?
No dose-response relationship has been detected in clinical trials. The SELECT trial used 2.4 mg weekly (the highest approved dose) for up to 5 years and found lower overall cancer incidence compared to placebo. There is no evidence that higher doses increase risk.
Should I stop semaglutide if a family member is diagnosed with cancer?
A family member's cancer diagnosis does not change your risk from semaglutide unless the diagnosis is medullary thyroid carcinoma (MTC) in a first-degree relative. Other cancer types in family members are not contraindications to semaglutide use.
Related guides
- Can Wegovy Cause Cancer? The Thyroid Signal, the Rodent Data, and What Actually Matters for Humans
- Does Ozempic Cause Thyroid Cancer? The Clinical Evidence and What the Black Box Warning Actually Means
- Has Anyone Got Thyroid Cancer from Ozempic? What the Evidence Actually Shows
- Has Anyone Gotten Thyroid Cancer From Ozempic? What the Evidence Actually Shows
- Does Ozempic Cause Cancer? An Evidence-Based Answer for 2026
- Does Mounjaro (Tirzepatide) Cause Cancer? The Evidence From 9,600+ Patient-Years of Data
Sources
- Hegedüs L et al. GLP-1 receptor agonists and thyroid C-cell biology: a review. Endocrine Reviews. 2020.
- Jastreboff AM et al. Tirzepatide once weekly for the treatment of obesity (SURMOUNT-1). New England Journal of Medicine. 2022.
- Wilding JPH et al. Once-weekly semaglutide in adults with overweight or obesity (STEP 1). New England Journal of Medicine. 2021.
- Lincoff AM et al. Semaglutide and cardiovascular outcomes in obesity without diabetes (SELECT). New England Journal of Medicine. 2023.
- Elashoff M et al. Pancreatitis, pancreatic, and thyroid cancer with glucagon-like peptide-1-based therapies. JAMA Internal Medicine. 2013.
- Monami M et al. Glucagon-like peptide-1 receptor agonists and pancreatic cancer: a meta-analysis. Diabetes Care. 2017.
- Pottegård A et al. Use of glucagon-like peptide 1 receptor agonists and risk of thyroid cancer: Scandinavian cohort study. Diabetologia. 2023.
- Nguyen K et al. Cholangiocarcinoma in patients treated with GLP-1 receptor agonists: a case series. Hepatology. 2024.
- Lundgren JR et al. Cancer incidence following bariatric surgery: a Danish nationwide cohort study. Obesity. 2023.
- National Cancer Institute. SEER Cancer Statistics Review: Thyroid Cancer. 2024.
- FDA Drug Safety Communication. FDA investigating reports of possible increased risk of pancreatitis and pre-cancerous findings of the pancreas from incretin mimetic drugs. 2013.
- European Medicines Agency. GLP-1 receptor agonists: PRAC recommends new measures to support safe use. 2023.
- Davies MJ et al. Gastrointestinal tolerability of tirzepatide and gastric emptying. Diabetes Care. 2023.
- American College of Gastroenterology. Guidelines for the diagnosis and management of gastroesophageal reflux disease. 2022.
Footer disclaimers
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. Ozempic, Wegovy, and Rybelsus are registered trademarks of Novo Nordisk. Mounjaro and Zepbound are registered trademarks of Eli Lilly and Company. Victoza and Saxenda are registered trademarks of Novo Nordisk. Byetta, Bydureon, and Trulicity are trademarks of their respective owners. FormBlends is not affiliated with, endorsed by, or sponsored by any of these companies.
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