Truqap (capivasertib) is a prescription drug that’s used to treat a certain type of breast cancer. Truqap can cause side effects that range from mild to serious. Examples include nausea, vomiting, and mouth sores.

Specifically, Truqap is used along with Faslodex (fulvestrant) in adults to treat a certain type of breast cancer. The cancer must have each of the following traits:

The active ingredient in Truqap is capivasertib. The drug comes as an oral tablet.

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

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

The following sections include more side effects of Truqap. Each person’s experience with side effects may differ.

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

You can learn more about high blood sugar and skin reaction in the “Side effects explained” section below.

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

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

Serious side effects have been reported with Truqap. These include:

You can learn more about high blood sugar and skin reaction in the “Side effects explained” section below.

If you develop serious side effects while taking Truqap, 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.

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

Allergic reaction

For some people, Truqap can cause an allergic reaction. But it’s not clear whether this side effect occurred in the drug’s studies.

In general, symptoms of 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 Truqap.

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

Your doctor can confirm whether you’ve had a serious allergic reaction to Truqap. If so, they may have you switch to a different treatment.

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

High blood sugar (hyperglycemia)

High blood sugar was a common side effect reported in studies of Truqap. Both mild and severe forms of high blood sugar have been reported. Mildly high blood sugar is more common. In rare situations, seriously high blood sugar can occur, which could lead to diabetic ketoacidosis.

Monitoring for symptoms of high blood sugar is important while taking Truqap. These symptoms can include:

  • increased amount and frequency of urine
  • increased or excessive thirst
  • increased appetite with weight loss
  • dry mouth
  • confusion
  • nausea

Factors that can increase the risk of high blood sugar when taking Truqap include current or past diabetes.

What might help

Before starting Truqap, your doctor will check your blood sugar level. They will also check your blood sugar regularly throughout your treatment. If you currently have or ever had diabetes, your doctor will check your blood sugar more frequently.

Be sure to monitor for the symptoms of high blood sugar noted above. If you develop any of these symptoms, talk with your doctor immediately. They’ll determine the severity of these symptoms. Depending on what they determine, they may want to hold, reduce, or discontinue your Truqap treatment.

Skin reaction

Skin reaction was a common side effect reported in studies of Truqap. Both mild and severe skin reactions have been reported in people taking Truqap. Mild skin reactions, such as dry skin and eczema, are more common. Rarely, serious skin reactions can occur, including hand-foot syndrome and erythema multiforme.

Serious skin reactions may cause symptoms such as:

  • skin lesions that are shaped like a target or bull’s-eye pattern
  • skin that is tender and peeling
  • skin blisters and sores
  • numbness and tingling in the palms of your hands and soles of your feet

What might help

Be sure to monitor for any of the symptoms of skin reaction noted above. If you develop any of these symptoms, talk with your doctor immediately. They’ll determine the severity of these symptoms. Depending on what they determine, they may want to hold, reduce, or discontinue your Truqap treatment.

Keeping track of side effects

During your Truqap 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 Truqap affects you. They can then use this information to adjust your treatment plan if needed.

Below is important information you should consider before taking Truqap.

Warnings

Truqap 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 Truqap is a good treatment option for you.

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