Key takeaways

  • Rybelsus commonly causes digestive side effects such as nausea, diarrhea, and abdominal pain.
  • Rybelsus carries a boxed warning regarding the risk of thyroid cancer.
  • Other serious side effects of this drug include low blood sugar level, kidney issues, and pancreas problems. However, these are rare.

Doctors prescribe Rybelsus together with a nutritious diet and exercise to manage blood sugar in adults with type 2 diabetes.

The active ingredient in Rybelsus is semaglutide. (An active ingredient is what makes a drug work.) The drug comes as a tablet that you swallow.

Keep reading to learn about the common, mild, and serious side effects that Rybelsus can cause.

Rybelsus has a boxed warning. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). For details, see the “Side effects explained” section later in this article.

With Rybelsus, some side effects are more common than others. The following list includes the more commonly reported side effects of this drug:

Nausea, vomiting, and diarrhea are more common when you first start taking Rybelsus or after dose increases. This is because your body needs time to get used to the medication. For most people, these side effects usually go away within a few days or weeks of dosage increases.

For more information about some of these side effects, see the “Side effects explained” section.

Rybelsus can cause mild side effects in some people. Examples of mild side effects that have been reported with Rybelsus include:

To learn more about some of these side effects, see the “Side effects explained” section.

In most cases, these side effects should be temporary. And some may be easily managed, too. But if you have any symptoms that are ongoing or that bother you, talk with your doctor or pharmacist. And do not stop using Rybelsus unless your doctor recommends it.

Rybelsus may cause mild side effects other than the ones listed here. See the Rybelsus prescribing information for details.

Do Rybelsus side effects go away?

Yes, most common and mild side effects of Rybelsus are expected to go away or ease within 4 weeks.

Many people experience mild digestive system problems, such as nausea or diarrhea, when starting Rybelsus or increasing the dose. These digestive side effects tend to ease or go away on their own as your body adjusts to the medication. This process can take up to a few weeks.

In rare cases, it’s also possible for these side effects to continue until you stop Rybelsus treatment.

To help prevent common digestive system side effects, your doctor will likely start you on a low Rybelsus dosage. Then, they’ll increase your dose slowly, no more than once every 30 days.

If you have persistent or bothersome side effects with Rybelsus, talk with your doctor. They can provide more specific details about how long these effects should last. They may also be able to recommend medications or other ways to help manage those side effects.

Serious side effects from Rybelsus are not common, but they can happen. Serious side effects that have been reported with Rybelsus include:

If you develop serious side effects while taking Rybelsus, call your doctor right away. If the side effects seem life threatening or if you think you’re having a medical emergency, immediately call 911 or your local emergency number.

For more information about some of these side effects, including the boxed warning, see the “Side effects explained” section.

Note: After the FDA approves a drug, it tracks and reviews side effects of the medication. Sharing your experience helps make medication safer for everyone by giving doctors and researchers more information about how the drug works in real life. If you develop a side effect while taking Rybelsus and want to tell the FDA about it, visit MedWatch or call 800-332-1088.

Allergic reaction

For some people, Rybelsus can cause an allergic reaction.

Studies of this drug did not report this side effect, but it has been reported since Rybelsus became available to prescribe.

In general, symptoms of an allergic reaction can be mild or serious.

What might help?

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. They may suggest a treatment to manage your symptoms and can determine whether you should keep taking Rybelsus.

If you have symptoms of a severe allergic reaction, such as swelling or difficulty breathing, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your doctor confirms you’ve had a serious allergic reaction to Rybelsus, they may have you switch to a different treatment.

Long-term side effects are possible with Rybelsus. This includes side effects that may start at any time while taking a drug, even if you’ve taken it for a long time. Some side effects of Rybelsus may not go away, even after you stop taking the drug.

Examples of long-term side effects reported with Rybelsus include:

To learn more about some of these side effects, see the “Side effects explained” section.

Talk with your doctor to learn more about possible side effects of Rybelsus and how long they may last.

Learn some frequently asked questions and answers about Rybelsus, including information about its side effects.

How much does Rybelsus cost? Are savings options available?

The cost of Rybelsus can vary, depending on your treatment plan, the pharmacy you use, and any insurance coverage you have. Here are a few tips for saving on the cost of this drug:

  • Comparing pharmacies: The price of Rybelsus may vary depending on which pharmacy you use, so it can help to compare prices across pharmacies to find the lowest cost.
  • Drug coupons: You may be able to find drug coupons on prescription discount websites that can reduce the cost of your medication. These coupons cannot be used with insurance copays or benefits, but the discounted price may be lower than what you would pay through insurance.
  • Financial assistance: Some websites provide details about drug assistance programs, ways to make the most of your insurance coverage, and links to savings cards and other services. Two such websites are:

Does the dose of Rybelsus I take, 3 milligrams (mg), 7 mg, or 14 mg, affect my risk of side effects?

It’s possible. In studies, some people chose to stop taking Rybelsus because of digestion-related side effects. (These included nausea, vomiting, abdominal pain, diarrhea, constipation, and loss of appetite.) Of these, more people taking a higher strength of Rybelsus (14 mg) stopped treatment compared with those taking a lower strength (7 mg).

All strengths of Rybelsus can cause mild or serious side effects. If you have concerns about side effects with your current dose of the drug, talk with your doctor.

Will Rybelsus cause hair loss?

No, Rybelsus should not cause hair loss. Studies of the drug did not report hair loss as a side effect.

However, type 2 diabetes, the condition that Rybelsus is used to treat, may be linked to hair loss. Other medications or medical conditions can also cause hair loss.

If you’ve experienced hair loss since starting Rybelsus, talk with your doctor. They may want to check for other causes and discuss your treatment options.

Does Rybelsus make you tired?

No, it should not. Studies of the drug did not report tiredness as a side effect.

Rybelsus is known to cause nausea and loss of appetite. These side effects can lead to not eating enough nutrient-dense calories, which can cause fatigue.

To ease nausea, consider trying different foods. Frequently eating snacks instead of three larger meals in a day may help lessen nausea. Choosing nutritious foods over foods with empty calories can give you more energy.

Type 2 diabetes can cause other medical conditions that may result in tiredness, such as heart disease. And some drugs that are used to treat these other conditions can make you feel fatigued, such as blood pressure medications.

If you’re feeling more tired than usual since you started taking Rybelsus, talk with your doctor. They’ll try to find out what’s causing this side effect so it can be treated. And they could change other medications that you might be taking.

Can you suddenly stop taking Rybelsus?

Yes, you can suddenly stop taking Rybelsus if you and your doctor decide that it is not safe or effective for you.

For example, if you develop a serious side effect from Rybelsus, your doctor will have you stop taking it right away. An example is pancreatitis.

If you want to stop taking Rybelsus, talk with your doctor first. It’s important that you have a plan in place to manage your blood sugar before stopping any diabetes treatment.

Learn more about some of the side effects Rybelsus may cause.

Weight loss

Rybelsus is not approved by the Food and Drug Administration (FDA) for weight loss. It’s approved to help with blood sugar management in adults with type 2 diabetes.

But the way Rybelsus works in your body may cause weight loss. This drug lowers your blood sugar by stimulating a certain hormone. This hormone slows down how fast your stomach empties after eating, which can help you feel full longer. As a result, you’re more likely to consume fewer calories, which can lead to weight loss.

Also, the more common side effects of Rybelsus are related to digestion. These side effects, which include nausea, abdominal pain, and reduced appetite, can cause weight loss. But most of these digestion-related side effects are temporary or can be easily managed.

And remember, this drug is meant to be part of a treatment plan that includes eating a balanced diet and exercising. These healthy practices can also contribute to weight loss.

What might help

For some people with type 2 diabetes, weight loss may be a beneficial side effect of Rybelsus. Losing weight can help improve blood sugar management and prevent type 2 diabetes from worsening. According to a 2020 study, it’s possible that weight loss may even help to reverse this type of diabetes.

If you’ve recently started taking Rybelsus, it’s common to experience nausea, vomiting, and diarrhea at first. Eating frequent snacks instead of three larger meals in a day may help lessen nausea. Choosing nutritious foods can help make sure that your body is still getting some nutrients.

Losing too much weight due to severe vomiting and diarrhea can be harmful. If you’re concerned about weight loss or severe digestion-related side effects from Rybelsus, talk with your doctor. They’ll likely recommend changes to your treatment plan.

Risk of thyroid cancer

Rybelsus has a boxed warning for the risk of thyroid cancer. A boxed warning is the most serious warning from the FDA.

In animal studies, semaglutide (the active ingredient in Rybelsus) caused thyroid tumors in mice and rats. But animal studies do not always reflect what will happen in humans.

It’s not known whether Rybelsus causes thyroid cancer in humans. To be safe, you should not take Rybelsus if:

If you take Rybelsus, you should be aware of the possible symptoms of thyroid cancer. These include:

  • a lump or growth in your neck
  • pain in your neck
  • difficulty swallowing
  • difficulty breathing
  • a hoarse voice that does not get better

What might help

Before you start Rybelsus, your doctor will want to know your health history. Tell your doctor whether you or someone in your family received a recent or previous diagnosis of MTC or MEN2. They’ll likely recommend a different medication for your type 2 diabetes.

If you develop any possible symptoms of thyroid cancer while taking Rybelsus, tell your doctor right away. They will screen you for this cancer.

If you have questions about your risk of thyroid cancer with Rybelsus, talk with your doctor.

Constipation

Constipation has been reported as a common side effect of Rybelsus.

Everyone experiences some constipation from time to time. But when it’s caused by a medication that you take daily, constipation can become severe. If untreated, constipation can lead to nausea, rectal bleeding, or an intestinal blockage.

Symptoms of constipation may include:

  • having fewer than three bowel movements in a week
  • having stools that are hard to pass
  • passing some stool, but feeling like there’s more that you cannot pass
  • abdominal pain

What might help

Constipation from Rybelsus might not go away on its own. You may need to take certain steps to relieve constipation and prevent it from coming back.

There are several over-the-counter laxatives that you can use to relieve constipation. Some work within days, others within minutes. Depending on how severe your constipation is, you may want quick relief. Here are a few examples of laxatives:

  • MiraLAX (polyethylene glycol 3350) is a powder that you mix into a liquid and then drink. It usually causes a bowel movement within 1 to 3 days.
  • Dulcolax (bisacodyl) rectal suppository usually causes a bowel movement within 15 to 60 minutes.
  • Fleet Saline Enema rectal enema usually causes a bowel movement within 1 to 5 minutes.

Home remedies may help prevent constipation naturally. Increasing your water intake, eating more vegetables, and exercising are a few ways to get your bowels moving regularly.

If you have questions about which option is best for your constipation, talk with your pharmacist or doctor.

Medical Perspective

Do certain foods increase the risk of digestive side effects from GLP-1 medications?

“Yes, certain foods can increase the probability of developing side effects from GLP-1 medications. For example, you may experience worsened nausea or bloating when you eat fried food or fast food.”

— Alex Nguyen, PharmD, RPh, CPh

Learn more about GLP-1 medications.

Quotes represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.

Rybelsus comes with several warnings.

Boxed warning: Risk of thyroid cancer

Rybelsus has a boxed warning about the risk of thyroid cancer. A boxed warning is the most serious warning from the FDA. For details, see the “Side effects explained” section.

Other warnings

Before taking Rybelsus, discuss your health history with your doctor. Rybelsus may not be right for you if you have certain medical conditions or other factors affecting your health. Be sure to talk with your doctor if any of the following apply to you:

Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.