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Generic name: pacritinib [ pak-RI-ti-nib ]
Brand name: Vonjo
Dosage form: oral capsule (100 mg)
Drug class: Multikinase inhibitors

Medically reviewed by on Aug 26, 2022. Written by Cerner Multum.

What is pacritinib?

Pacritinib is used to treat myelofibrosis in adults.

Pacritinib may also be used for purposes not listed in this medication guide.

Pacritinib side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Pacritinib may cause serious side effects. Call your doctor at once if you have:

Common side effects of pacritinib may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.


Use only as directed. Tell your doctor if you use other medicines or have other medical conditions or allergies.

Before taking this medicine

Some drugs should not be used with pacritinib. Your treatment plan may change if you also use:

Tell your doctor if you have ever had:

It is not known if pacritinib will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

It may be harder for you to get a woman pregnant while you are using pacritinib.

Do not breastfeed while using this medicine, and for at least 2 weeks after your last dose.

How should I take pacritinib?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

If you take other kinase inhibitors such as fedratinib or ruxolitinib you should not stop using these medicines suddenly before you start taking pacritinib. Follow your doctor's instructions about tapering your dose.

Pacritinib is usually taken by mouth twice every day with or without food.

Swallow the capsule whole and do not crush, chew, break, or open it.

You will need blood tests before you start taking pacritinib and during treatment.

Your treatment with pacritinib may be delayed or permanently discontinued if you have certain side effects.

Store at room temperature away from moisture, heat, and light.

Pacritinib dosing information

Usual Adult Dose for Myelofibrosis:

200 mg orally 2 times a day

Use: Treatment of patients with intermediate or high-risk primary or secondary (post-polycythemia vera OR post-essential thrombocythemia) myelofibrosis (MF) with a platelet count less than 50 times 10(9)/L (50 x 10(9)/L)

What happens if I miss a dose?

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking pacritinib?

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

What other drugs will affect pacritinib?

Sometimes it is not safe to use certain medicines at the same time. Some drugs can affect your blood levels of other drugs you use, which may increase side effects or make the medicines less effective.

Other drugs may affect pacritinib, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all other medicines you use.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.