Orladeyo (berotralstat) is a prescription drug used to prevent swelling attacks caused by hereditary angioedema (HAE). Orladeyo can cause side effects ranging from mild to serious. Examples include abdominal pain, vomiting, and diarrhea.

Orladeyo is used in adults and in children ages 12 years and older to prevent swelling attacks caused by HAE.

The active ingredient in Orladeyo is berotralstat. (An active ingredient is what makes a drug work.) The drug comes as an oral capsule.

Keep reading to learn about the common, mild, and serious side effects that Orladeyo can cause. For a general overview of the drug, including details about its uses, see this article.

Note: Orladeyo should not be used to treat a swelling attack that’s currently happening. Instead, Orladeyo is taken regularly to help prevent attacks from occurring.

Some people may experience mild to serious side effects during their Orladeyo treatment. Examples of Orladeyo’s commonly reported side effects include:

Mild side effects have been reported with Orladeyo. These include:

Mild side effects may begin shortly after beginning Orladeyo treatment and may go away over time. But if you have ongoing or bothersome symptoms, talk with your doctor or pharmacist. And you should not stop taking Orladeyo unless your doctor recommends it.

Orladeyo may cause mild side effects other than those listed above. See the drug’s prescribing information for details.

* To learn more about this side effect, see the “Side effects explained” section below.
† An allergic reaction is possible after taking Orladeyo, but this side effect wasn’t reported in studies.

Rare but serious side effects may occur with Orladeyo. These include:

If you develop serious side effects while taking Orladeyo, 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.

* To learn more about this side effect, see the “Side effects explained” section below.
† An allergic reaction is possible after taking Orladeyo, but this side effect wasn’t reported in studies.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks side effects of the medication. If you’d like to notify the FDA about a side effect you’ve had with Orladeyo, visit MedWatch.

Get answers to some frequently asked questions about Orladeyo’s side effects.

Are side effects of Orladeyo similar to those seen with Takhzyro?

Orladeyo and Takhzyro are both used to prevent swelling attacks from hereditary angioedema (HAE). These drugs can cause some similar mild side effects, including headache, skin rash, and diarrhea.

Orladeyo is an oral capsule, while Takhzyro is given as an injection under your skin. Takhzyro can cause injection site reactions, such as pain or skin discoloration, that aren’t side effects of Orladeyo.

To learn more about Takhzyro’s side effects, see this article.

How can I manage digestive problems from Orladeyo?

In studies, abdominal pain, vomiting, and diarrhea were common side effects. For some people, these side effects may begin shortly after starting treatment and may continue during treatment. But in other people, these side effects may lessen or go away over time.

Taking Orladeyo with bland food may help ease nausea, vomiting, and diarrhea. For heartburn, you may take over-the-counter (OTC) acid reducers such as famotidine (Pepcid AC) or calcium carbonate chewable. However, some OTC medications may interact with Orladeyo, so check with your pharmacist before taking any OTC drugs with Orladeyo.

If your symptoms don’t improve, you can ask your doctor about lowering your dose of Orladeyo.

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

Increased liver enzymes

In studies of Orladeyo, increased liver enzymes were a rare side effect in people taking the drug.

Having a high level of liver enzymes could be a sign of liver damage. It may not cause noticeable symptoms, so your doctor may order regular blood tests to check for increased liver enzymes during your Orladeyo treatment. But symptoms of liver damage you should watch for include:

  • jaundice (yellowing of your skin or the whites of your eyes)
  • dark urine
  • unusual-colored stool (very light or dark)
  • itchy skin
  • abdominal pain
  • reduced appetite
  • nausea
  • vomiting
  • fatigue (low energy)

If you already have liver problems or you take other medications also broken down by the liver, you may have a higher risk of increased liver enzymes with Orladeyo.

What might help

If you have increased liver enzymes while taking Orladeyo, your doctor may reduce your daily dose from 150–110 milligrams (mg).

Heart rhythm problems

Taking more than one Orladeyo capsule in 24 hours can cause a heart rhythm issue known as long QT syndrome.

Studies of Orladeyo showed that in rare cases, taking more than the maximum recommended dosage of 150 mg daily can cause this life threatening side effect.

Long QT syndrome may cause symptoms such as:

What might help

It’s important that you take Orladeyo exactly as prescribed by your doctor so you don’t take more than the recommended daily dosage. You may want to use a calendar to check off doses or a pill box to track your doses.

Call your doctor or pharmacist immediately if you take an extra dose.

If you develop any symptoms of long QT syndrome, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

Allergic reaction

Like most drugs, Orladeyo can cause an allergic reaction in some people. However, this side effect wasn’t reported in studies.

Symptoms can be mild to serious and can include:

  • skin rash
  • itchiness
  • flushing (temporary warmth, redness, or deepening of skin color)
  • swelling under your skin, usually in your eyelids, lips, hands, or feet
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

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. Examples include:

  • an antihistamine you swallow, such as Benadryl (diphenhydramine)
  • a product you apply to your skin, such as hydrocortisone cream

If your doctor confirms you’ve had a mild allergic reaction to Orladeyo, they’ll decide whether you should continue taking it or switch to a different treatment.

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

Keeping track of side effects

During your Orladeyo treatment, consider taking notes on any side effects you’re having. You can then share this information with your doctor. This is especially helpful when you first start taking a new drug or using a combination of treatments.

Your side effect notes can include things such as:

  • what dose of the drug you were taking when you had the side effect
  • how soon you had the side effect after starting that dose
  • what your symptoms were
  • how your symptoms affected your daily activities
  • what other medications you were taking
  • any other information you feel is important

Keeping notes and sharing them with your doctor will help them learn more about how Orladeyo affects you. They can then use this information to adjust your treatment plan if needed.

Below is important information you should consider before taking Orladeyo.


Orladeyo can sometimes cause harmful effects in people who have certain conditions. This is known as a drug-condition interaction. Other factors may also affect whether Orladeyo is a good treatment option for you.

Talk with your doctor about your health history before you take Orladeyo. Be sure to tell them if any of the following factors apply to you:

  • You have severe kidney problems or are receiving dialysis.
  • You have liver problems.
  • You’ve had a previous allergic reaction to Orladeyo.
  • You’re pregnant.
  • You’re breastfeeding.

It’s also important to talk with your doctor or pharmacist about other prescription medications, vitamins, herbals, or over-the-counter medications you’re taking. Orladeyo can interact with certain drugs and cause new or worsening side effects.

Alcohol and Orladeyo

There are no known interactions between alcohol and Orladeyo. But alcohol and Orladeyo can both cause heartburn, vomiting, and headache. So, combining the two may raise your risk of experiencing these side effects.

If you have questions about consuming alcohol while taking Orladeyo, talk with your doctor or pharmacist.

Pregnancy and breastfeeding with Orladeyo

It’s not known whether it’s safe to take Orladeyo during pregnancy or while breastfeeding.

If you’re pregnant or breastfeeding, or planning to become pregnant or to breastfeed, talk with your doctor before taking Orladeyo.

Like most drugs, Orladeyo can cause some side effects that range from mild to serious. However, most are temporary and go away after a few days to weeks. If you have questions about side effects that this drug can cause, talk with your doctor.

Examples of questions to help get you started include:

  • What are the side effects I should watch for while taking Orladeyo?
  • Can I treat side effects of Orladeyo with over-the-counter medications?
  • What problems could I experience from Orladeyo if I’m having dialysis?

To learn more about Orladeyo, see these articles:

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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.