Research isn’t clear on whether semaglutide causes thyroid tumors. But people with a history of thyroid cancer may want to avoid using this diabetes and weight loss medication.

Semaglutide is in a class of medications known as glucagon-like peptide 1 (GLP-1) agonists. Brand names of semaglutide include Ozempic, Rybelsus, and Wegovy. Maybe you’re one of the growing number of people using these medications.

Any medication carries possible risks. There has been some research suggesting that semaglutide may increase the risk of thyroid cancer.

Here’s more about the possible connections between thyroid health and semaglutide.

Many factors raise or lower someone’s risk of developing cancer. It can be hard to pinpoint whether something truly causes cancer. In animal studies, semaglutide was shown to cause thyroid tumors.

The same result wasn’t seen in humans, but there’s still a chance that semaglutide could increase this risk. The safety profile for semaglutide recommends that anyone with a personal or family history of some thyroid cancers shouldn’t use semaglutide.

A 2022 study compared people in France who did and didn’t take semaglutide, and found higher rates of thyroid cancer in people who used semaglutide, especially after 1 to 3 years of use.

A 2023 research review aimed to further explore links between semaglutide and all types of cancer. But it didn’t find any association between semaglutide and an increased risk of cancer.

The European Medicines Agency’s (EMA) Pharmacovigilance Risk Assessment Committee in October 2023 examined available evidence and determined there’s no link between GLP-1 agonists and thyroid cancer.

If you have a diagnosis of cancer, you and your healthcare professional will discuss the next steps when it comes to the medications you currently take. Some may be discontinued.

Known side effects of semaglutide include nausea, vomiting, and early satiety. Many people with cancer will also experience similar effects from the cancer and its treatment. It may not make sense to stay on this medication if it will make those symptoms worse.

One small study from 2023 suggested that semaglutide increased the action of natural killer cells in the body. These cells may be involved in preventing cancer by identifying and destroying abnormal cancer cells. There’s much more to learn and understand about cancer and its treatments. At this point, semaglutide isn’t a standard part of cancer treatment.

In rodent studies, semaglutide caused thyroid tumors. Human studies didn’t show the same results. Safety information for semaglutide recommends that people with a personal or family history of some thyroid tumors shouldn’t take semaglutide.

A research review from 2022 looked at semaglutide use and any link to thyroid cancer and other thyroid conditions.

The other thyroid conditions that were included in the research were:

  • hyperthyroidism (overactive thyroid)
  • hypothyroidism (underactive thyroid)
  • thyroiditis (inflammation in the thyroid)
  • thyroid mass (noncancerous growths)
  • goiter (swollen thyroid)

The research found that semaglutide use didn’t increase the risk of any of those thyroid disorders.

Beyond concerns about thyroid health, semaglutide has several side effects. They include:

  • nausea and vomiting
  • diarrhea or constipation
  • early feelings of fullness
  • slower digestion
  • increased burping
  • malnutrition due to very low food intake
  • reactions at injection sites
  • an increased risk of gallstones

Studies are conflicting about a link between semaglutide and pancreatitis or pancreatic cancer. At this point, semaglutide doesn’t seem to increase the risk, but longer-term studies would be helpful.

Whether you start or stay on a medication is an important decision. It’s smart to discuss any concerns or questions with your healthcare professional.

Semaglutide caused thyroid tumors in rodents during research trials. Anyone with a personal or family history of medullary thyroid carcinoma shouldn’t use this medication. This type of cancer is very rare.

Many people gave a difficult time with the side effects of semaglutide. If they’re affecting your quality of life, please let your healthcare professional know. The medication might not be a good fit for you.

If you do develop cancer while you’re taking Ozempic or after you stop Ozempic, you and your doctor will discuss your next steps. If you are still taking Ozempic, you can discuss whether it makes sense to stay on Ozempic or whether you’ll stop taking the medication.

The Food and Drug Administration (FDA) keeps a database of adverse effects to track potential risks of medications. This is known as the FDA Adverse Event Reporting System (FAERS). Depending on your case, you and your healthcare professional may decide to file a report.

The type of cancer that was seen in semaglutide animal studies is medullary thyroid carcinoma. It’s quite rare. Only about 1,000 people receive a diagnosis of this form of cancer every year in the United States.

Since it’s rare, it’s hard to get accurate survival data. Survival will largely depend on the size of the tumor and whether the cancer has spread.

Signs of thyroid cancer include a lump in your throat. You may start to experience changes in your voice if the tumor is pressing on your vocal cords. If you notice changes in your voice or breathing, it’s smart to check in with your healthcare professional.

The rates of semaglutide use are way up over the past few years. As with any medication, there are always possible risks. Researchers found that semaglutide caused thyroid cancer in rodents. This wasn’t seen in human studies.

If you have a personal or family history of medullary thyroid carcinoma, you shouldn’t use semaglutide. Common side effects of semaglutide include nausea, early fullness, vomiting, and diarrhea.

Make sure you discuss any concerns or questions about semaglutide with your healthcare professional to make sure it’s right for you.