Gemtesa (vibegron) is a brand-name oral tablet that’s prescribed for overactive bladder in adults. As with other drugs, Gemtesa can cause side effects. These include headache, urinary tract infection (UTI), and nausea.

Gemtesa can cause certain side effects, some of which are more common than others. These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

These are just a few of the more common side effects reported by people who took Gemtesa in clinical trials:

* For more information about this side effect, see “Side effect specifics” below.

Mild side effects can occur with Gemtesa use. This list doesn’t include all possible mild side effects of the drug. For more information, you can refer to Gemtesa’s prescribing information.

Mild side effects that have been reported with Gemtesa include:

These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. If you develop a side effect while taking Gemtesa and want to tell the FDA about it, visit MedWatch.

* For more information about this side effect, see “Side effect specifics” below.
† An allergic reaction is possible after taking Gemtesa. However, it’s not clear whether this side effect occurred in clinical trials. To learn more, see the “Side effect specifics” section below.

Gemtesa may cause serious side effects. However, serious side effects aren’t common in people taking Gemtesa. The list below may not include all possible serious side effects of the drug. For more information, you can refer to Gemtesa’s prescribing information.

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

Serious side effects that have been reported and their symptoms include:

  • Urinary retention (difficulty or inability to completely empty your bladder). Symptoms can include:
    • difficulty urinating
    • frequent urge to urinate
    • straining to urinate
    • needing to urinate again right after urinating
  • Severe allergic reaction.*

* An allergic reaction is possible after taking Gemtesa. However, it’s not clear whether this side effect occurred in clinical trials. To learn more, see the “Side effect specifics” section below.

Gemtesa may cause several side effects. Here are some frequently asked questions about the drug’s side effects and their answers.

Can Gemtesa cause weight loss?

No, you shouldn’t experience weight loss from taking Gemtesa. Weight loss was not a reported side effect in Gemtesa’s clinical trials.

However, it’s possible to experience weight loss from other side effects of Gemtesa. For example, the drug may cause nausea or diarrhea. If you have severe nausea, you may not be able to eat as you typically would. In turn, this can cause weight loss. In addition, severe diarrhea may also lead to weight loss.

If you notice weight loss that’s severe or bothersome while taking Gemtesa, talk with your doctor. They can help determine what may be causing this condition. They can also recommend the best ways to manage your weight.

How do side effects of Gemtesa compare with those seen with Myrbetriq?

Gemtesa and Myrbetriq (mirabegron) are both medications that can be prescribed to treat an overactive bladder (OAB). Some side effects have been reported in both drugs. However, other side effects are only expected to occur with one drug or the other.

For example, the following side effects are common in both Gemtesa and Myrbetriq:

However, certain side effects of Gemtesa, such as hot flashes, did not occur in Myrbetriq’s clinical trials. Other side effects, such as high blood pressure, have been reported with Myrbetriq but not Gemtesa.

If you have OAB, talk with your doctor to find out which treatment option may be best for you. For more information about Myrbetriq’s side effects, see this article.

Learn more about some of the side effects that Gemtesa may cause. To find out how often side effects occurred in clinical trials, see the prescribing information for Gemtesa.

Constipation

It’s possible for Gemtesa to cause constipation. However, this wasn’t a commonly reported side effect in the drug’s clinical trials.

Symptoms of constipation may include:

  • straining during bowel movements
  • hard stool
  • less frequent bowel movements

What you can do

If you experience constipation during your treatment with Gemtesa, talk with your doctor. They can help determine whether Gemtesa is causing this side effect. In some cases, they may recommend treating constipation with an over-the-counter medication, such as MiraLAX (polyethylene glycol 3350).

Urinary tract infection

Gemtesa may cause a urinary tract infection (UTI) during your treatment. In fact, a UTI was one of the most common side effects reported in Gemtesa’s clinical trials.

If you experience symptoms of a UTI during treatment with Gemtesa, talk with your doctor. These symptoms may include:

What you can do

If you develop symptoms of a UTI, contact your doctor. They can order a urine test to determine whether you have a UTI. If you do develop this infection while taking Gemtesa, your doctor will likely prescribe an antibiotic to treat it.

Allergic reaction

As with most drugs, Gemtesa can cause an allergic reaction in some people. However, it’s not clear whether this side effect occurred in clinical trials.

Symptoms can be mild or serious and can include:

  • skin rash
  • itching
  • flushing
  • swelling under your skin, typically in your eyelids, lips, hands, or feet
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

What you can do

For mild symptoms of an allergic reaction, call your doctor right away. They may recommend ways to ease your symptoms and determine whether you should keep taking Gemtesa. However, if your symptoms are serious and you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Be sure to talk with your doctor about your health history before you take Gemtesa. This drug may not be the right treatment option for you if you have certain medical conditions or other factors that affect your health. These are considered drug-condition or drug-factor interactions. The conditions and factors to consider include:

Liver problems. If you have severe liver problems, talk with your doctor before you start taking Gemtesa. This drug hasn’t been studied in people with severe liver conditions. For this reason, it’s not known whether Gemtesa is safe in this case.

Gemtesa is removed from your body by your kidneys and liver. If you have liver problems, it’s possible for the drug to build up in your body. In turn, this can increase your risk of side effects. Your doctor will help determine whether Gemtesa is safe with your condition.

Kidney problems. Gemtesa hasn’t been studied in people with severe kidney problems. For this reason, it’s not known whether the drug is safe to take with these conditions.

Gemtesa is removed from your body by your kidneys and liver. If you have kidney problems, it’s possible for Gemtesa to build up in your body. This can increase your risk of side effects during treatment with this drug. If you have kidney problems, talk with your doctor before you start taking Gemtesa.

Allergic reaction. If you’ve had an allergic reaction to Gemtesa or any of its ingredients, your doctor will likely not prescribe Gemtesa. Ask your doctor what other medications may be better options for you.

Difficulty emptying your bladder. Before taking Gemtesa, tell your doctor if you have any problems with urination. This can include difficulty starting or maintaining a stream of urine or difficulty emptying your bladder. These may be signs of urinary retention. It’s possible for Gemtesa to cause urinary retention. If you already have this condition, taking Gemtesa may worsen it. Your doctor can help determine whether Gemtesa is safe for you to take.

Pregnancy or breastfeeding. If you’re pregnant or breastfeeding your child, it’s not known whether Gemtesa is safe for you. At this time, there aren’t any clinical trials on the safety of Gemtesa when taken during pregnancy or while breastfeeding. If you’re pregnant, breastfeeding, or planning for either, talk with your doctor. They’ll advise whether this drug is safe for you to take.

Alcohol consumption. If you drink alcohol, Gemtesa is likely safe for you to take. However, drinking alcohol can cause more frequent urination. For this reason, alcohol consumption during treatment may worsen symptoms of an overactive bladder (OAB). (Gemtesa is prescribed to treat OAB.) As such, your doctor may recommend avoiding alcohol while you take Gemtesa. If you drink alcohol, ask your doctor how much, if any, is safe to drink during treatment.

Side effects from Gemtesa are typically mild, but it’s also possible for serious side effects to occur. However, serious side effects are not common.

If you’d like to learn more about Gemtesa, talk with your doctor or pharmacist. They can help answer any questions you have about side effects from taking the drug.

Besides talking with your doctor, you can do some research on your own. These articles might help:

  • More information about Gemtesa. For details about other aspects of Gemtesa, refer to this article.
  • Cost. If you’d like to learn about Gemtesa and cost, see this article.
  • Dosage. For information about the dosage of Gemtesa, view this article.
  • A look at overactive bladder (OAB). For details about OAB, see our list of OAB articles.

Disclaimer: Medical News Today 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.