Key takeaways

  • Common side effects of Fanapt may include dizziness, dry mouth, fatigue, sleepiness, and a stuffy nose. More serious, less common side effects may involve metabolic changes, blood disorders, heart problems, and tardive dyskinesia.
  • Fanapt has an FDA boxed warning about the increased risk of death in older adults with dementia-related psychosis, so it is usually avoided for these individuals.
  • Before starting Fanapt, discuss your health history with your doctor, especially if you have conditions like seizure disorders, diabetes, liver problems, or heart issues.

Fanapt (iloperidone) is a brand-name oral tablet prescribed to treat schizophrenia and bipolar disorder in adults. As with other drugs, Fanapt can cause side effects.

X drug has a boxed warning for increased risk of death in certain older adults. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). For details, see the “Managing side effects” section.

Fanapt 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 Fanapt in clinical trials:

Mild side effects can occur when taking Fanapt. This list doesn’t include all possible mild side effects of the drug. For more information, see Fanapt’s prescribing information.

Mild side effects that have been reported with Fanapt include:

  • dizziness
  • fatigue
  • dry mouth
  • sleepiness
  • abdominal pain
  • changes in weight
  • stuffy nose
  • skin rash
  • joint or muscle pain or stiffness
  • diarrhea
  • restlessness
  • urinary incontinence
  • sexual side effects, such as erectile dysfunction

These side effects may be temporary, lasting a few days to weeks. However, if the side effects continue, worsen, or become too difficult to tolerate, 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. Sharing your experience helps make medications 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 Fanapt and want to tell the FDA about it, visit MedWatch or call 800-FDA-1088.

Fanapt may cause serious side effects, but they aren’t common. The following list may not include all possible serious side effects of the drug. For more information, refer to Fanapt’s prescribing information.

If you develop serious side effects while taking Fanapt, 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 of Fanapt that have been reported include:

For more information about some of these side effects, see “Managing side effects.”

Allergic reaction

For some people, Fanapt can cause an allergic reaction.

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 Fanapt, your doctor may recommend taking a different medication instead.

While taking Fanapt, you may be able to take steps to make side effects easier to manage.

If you have problems with side effects that do not go away or become worse, talk with your doctor or pharmacist. They can discuss options for managing side effects or other treatment options.

Boxed warning: Increased risk of death in certain older adults

Fanapt has a boxed warning for increased risk of death in certain older adults. A boxed warning is the most serious warning from the FDA.

Antipsychotic drugs, including Fanapt, may increase the risk of death when used in older adults to treat psychosis related to dementia.

Fanapt is used to treat symptoms of schizophrenia, such as psychosis (a loss of touch with reality). Dementia can also cause symptoms of psychosis. However, Fanapt is not approved to treat dementia-related psychosis.

What you can do

Because of an increased risk of death, doctors typically won’t prescribe Fanapt to treat dementia-related psychosis in older adults. Talk with your doctor to learn more about this warning or other treatment options available for dementia-related psychosis.

Orthostatic hypotension

Orthostatic hypotension was a commonly reported side effect of Fanapt in clinical trials. This is when there is a sudden drop in blood pressure when changing positions, such as when moving from sitting to standing. This side effect is more likely to occur if the dose of Fanapt is increased too quickly. Symptoms can include:

  • lightheadedness
  • dizziness
  • rapid heart rate
  • fainting

What you can do

Your doctor will likely start you on a low dose and slowly increase the dose to reduce your risk of orthostatic hypotension. Be sure to drink plenty of liquids to avoid dehydration, which can increase your risk of this side effect. To help prevent or manage orthostatic hypotension, there are a few other things you can try:

  • When getting out of bed, sit on the edge of the bed for a minute before standing up.
  • Avoid strenuous activity during hot weather.
  • Limit alcohol consumption.

It’s important to tell your doctor if you have a history of heart problems. Also be sure to tell them about all the medications you take before you start Fanapt. Your doctor may want to monitor you more closely. If you have episodes of orthostatic hypotension that are bothersome or happening more often, tell your doctor right away.

Take note of the following important information to consider before taking Fanapt.

Boxed warning: Increased risk of death in certain older adults

This drug has a boxed warning for increased risk of death in certain older adults. For details, see the “Managing side effects” section.

Other precautions

Be sure to talk with your doctor about your health history before you take Fanapt. This drug may not be the right treatment for you if you have certain medical conditions or other factors that affect your health. These include:

Seizure disorder: If you have a seizure disorder or a history of seizures, talk with your doctor before you start taking Fanapt. Taking Fanapt may increase your risk of seizures and could worsen your condition. Your doctor can determine whether treatment with Fanapt is the right choice for you.

Diabetes: The use of Fanapt can cause hyperglycemia (high blood sugar levels). If you have diabetes, it may be harder to manage your blood sugar during treatment with Fanapt. Your doctor will likely monitor your blood sugar more closely while you’re taking the medication. They may need to adjust your diabetes medications if your blood sugar is high.

Long QT syndrome: The use of Fanapt can cause a change in heart rhythm or heart rate that is known as long QT syndrome. If you have a history of heart problems or have congenital long QT syndrome, talk with your doctor before taking Fanapt. You may be at an increased risk of heart problems. Your doctor can decide whether Fanapt is a safe treatment option for you or may recommend a different medication for you.

Liver problems: Tell your doctor if you have liver problems, such as cirrhosis or liver failure. Fanapt isn’t recommended for people with severe liver problems. If you have moderate liver problems, your doctor will likely prescribe a lower dose of Fanapt for you.

Heart problems: If you have heart problems, such as an abnormal heart rhythm or heart failure, you may be at a higher risk for heart problems during treatment with Fanapt. Be sure to tell your doctor about any heart problems you have before taking Fanapt.

High or low blood pressure: Fanapt can cause changes in blood pressure. Tell your doctor if you have either high or low blood pressure. Taking Fanapt can worsen your condition. Talk with your doctor to determine whether Fanapt is a safe treatment option for you.

Low potassium or magnesium levels: If you have low potassium or magnesium levels or had them in the past, you may be at a higher risk for heart problems such as long QT syndrome. Your doctor will want to monitor your potassium and magnesium levels before and during treatment with Fanapt.

High cholesterol: Fanapt may increase your cholesterol or triglyceride levels. If you have high cholesterol or triglycerides, taking Fanapt can further increase them. Your doctor will likely want to monitor your cholesterol during treatment with Fanapt. They may need to prescribe a cholesterol medication to reduce the risk of further complications.

Trouble managing body temperature: Treatment with Fanapt can affect how your body manages body temperature. Conditions such as exposure to extreme heat, dehydration, or strenuous exercise can increase the risk of an elevation in body temperature. If you’re prone to these conditions, talk with your doctor about the risks and benefits of taking Fanapt.

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

Pregnancy or breastfeeding: Fanapt may not be safe to take if you are pregnant or breastfeeding. Talk with your doctor before taking Fanapt if you’re pregnant, planning to become pregnant, or breastfeeding. They can discuss the risks and benefits of using Fanapt while pregnant or breastfeeding.

If you become pregnant while taking Fanapt, you and your doctor should consider reporting your pregnancy to the National Pregnancy Registry for antipsychotic drugs. This registry helps gather information about how exposure to these drugs may affect pregnancy outcomes. For more information, you can call 866-961-2388, visit the website, or talk with your doctor.

Alcohol consumption: If you drink alcohol, you should not drink it during treatment with Fanapt. Alcohol can worsen your condition or increase the risk of certain side effects, such as sleepiness. Talk with your doctor if you have questions about alcohol use while taking Fanapt.

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.