Vowst (fecal microbiota spores, live-brpk) is a brand-name oral capsule that’s prescribed to help prevent Clostridioides difficile (C. diff) infection returning after antibiotic treatment in certain adults. As with other drugs, Vowst can cause side effects, such as bloating and fatigue.

Vowst 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 Vowst in clinical trials:

  • abdominal bloating*
  • fatigue
  • constipation*
  • chills
  • diarrhea

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

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

Mild side effects that have been reported with Vowst include:

  • abdominal bloating*
  • fatigue
  • constipation*
  • diarrhea
  • flatulence (gas)
  • nausea
  • chills

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 Vowst and want to tell the FDA about it, visit MedWatch.

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

No serious side effects were reported in clinical trials of Vowst.

If you develop serious side effects while taking Vowst, 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.

ALLERGIC REACTION

For some people, Vowst can cause an allergic reaction. But this side effect wasn’t reported in the drug’s studies.

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

Ways to manage

For mild allergic reaction symptoms, such as a mild rash, call your doctor right away. They may recommend treatments to help manage your symptoms. They’ll also let you know whether you should keep taking the medication.

For severe allergic reaction symptoms, such as swelling or trouble breathing, call 911 or your local emergency number right away. These symptoms require immediate medical care because they can become life threatening. If you’ve had a serious allergic reaction to Vowst, your doctor may recommend taking a different medication instead.

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

How long do Vowst side effects last?

Side effects from Vowst typically last only a few days. In clinical trials, Vowst side effects lasted 5 days or less on average.

Keep in mind that Vowst can affect different people in different ways. If you have side effects that last longer than a few days or seem severe, talk with your doctor.

Is Vowst safe to take?

Yes, the Food and Drug Administration (FDA) considers Vowst to be safe for helping to prevent Clostridioides difficile (C. diff) infection coming back after antibiotic treatment in adults with recurring C. diff infection. No serious side effects have been reported with Vowst.

Vowst is made from fecal matter obtained from healthy donors. Although people with infectious diseases are not allowed to donate fecal matter, there’s a small risk that Vowst may contain germs that could cause infections. However, no cases of transmitted infections have been reported in people who have taken Vowst.

If you have questions about the safety of Vowst, talk with your doctor or pharmacist.

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

Abdominal bloating

You may have bloating of your abdomen after taking Vowst. Abdominal bloating was very commonly reported in clinical trials of Vowst. Most cases started within 10 days of starting treatment. Bloating was typically mild or moderate and improved within a few days.

Symptoms of bloating can include:

  • swelling of your abdomen
  • feeling of fullness
  • abdominal discomfort or pain
  • gas

What you can do

If you have bloating after taking Vowst, it may help to drink plenty of water. Drinking peppermint tea or taking peppermint oil capsules can also help some people. This side effect may also be eased by doing gentle exercises, such as walking or yoga. Taking a warm bath or using a heating pad can also be helpful. Learn more about other options in this tips for reducing bloating article.

If you have bloating, you should avoid fizzy drinks and chewing gum because these can make your symptoms worse.

If you have bothersome bloating and these measures don’t help, talk with your doctor or pharmacist. They may recommend an over-the-counter medication to help relieve your symptoms. For example, antacids and medications containing simethicone can help relieve bloating related to excess gas.

If you have bloating that’s severe or doesn’t get better within a few days, talk with your doctor.

Constipation

You may have constipation after taking Vowst. In clinical trials, constipation was commonly reported in people who took Vowst. Most cases started within 10 days of starting treatment. Constipation was typically mild or moderate and improved within a few days.

Symptoms of constipation can include:

  • hard stools that are difficult or painful to pass
  • straining when having a bowel movement
  • feeling that your bowel is not fully empty
  • having fewer than three bowel movements per week
  • abdominal discomfort or bloating

What you can do

If you have constipation after taking Vowst, there are some lifestyle measures you can take to help ease this side effect. For example, it may help to:

  • increase your fiber intake, for example, by eating more fruits, vegetables, and whole grains
  • drink plenty of water
  • participate in gentle exercise, such as walking

If these measures don’t help your constipation, ask your doctor if they recommend taking a laxative.

If you have constipation that’s severe or doesn’t get better after a few days, talk with your doctor.

Before taking Vowst, discuss your health history with your doctor. Vowst 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:

  • food allergies
  • previous allergic reaction to this or a similar drug
  • kidney problems
  • pregnancy
  • breastfeeding

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.