Ruxolitinib

Pronunciation: RUX-oh-LI-ti-nib
Generic name: ruxolitinib
Brand names: Jakafi, Opzelura (cream)
Dosage form: oral tablet (5 mg, 10 mg, 15 mg, 20 mg, 25 mg), topical cream (1.5%)
Drug class: Multikinase inhibitors

Medically reviewed by Carmen Pope, BPharm. Last updated on May 25, 2025.

What is ruxolitinib?

Ruxolitinib (oral) is used to treat certain types of myelofibrosis (MF), polycythemia vera (PV), and graft-versus-host disease. The brand name is Jakafi, and it is an oral tablet that is taken twice a day. 

Topical ruxolitinib is used for atopic dermatitis (eczema) and nonsegmental vitiligo. The brand name is Opzelura, and it is a cream that is applied thinly twice a day. This medication guide covers oral ruxolitinib only.

Ruxolitinib works by blocking specific proteins called JAK1 and JAK2 that send "grow and multiply" signals to blood cells and immune cells. By stopping these signals, ruxolitinib reduces abnormal cell growth in blood cancers like myelofibrosis/polycythemia vera and decreases harmful inflammation in graft-versus-host disease and skin conditions such as atopic dermatitis and nonsegmental vitiligo by suppressing inflammatory cytokines. It belongs to the drug class called kinase inhibitors.

Ruxolitinib first gained FDA approval on November 16, 2011, under the brand name Jakafi. The topical formulation of ruxolitinib, Opzelura cream, was FDA approved on September 21, 2021. There is no generic form of the tablets or cream available.

FDA approvals and uses

Oral ruxolitinib is FDA-approved to treat:

• Intermediate or high-risk myelofibrosis (MF) (includes primary MF, post-polycythemia vera MF, and post-essential thrombocytopenia MF) in adults
• Polycythemia vera (PV) in adults who have had an inadequate response to, or are intolerant of, hydroxyurea
• Steroid-refractory acute graft-versus-host disease (aGVHD) in adults and children aged 12 years and older
• Chronic graft-versus-host disease (cGVHD) in adults and children aged 12 years and older after failure of one or two lines of systemic therapy.

It is not known if ruxolitinib is safe or effective in children with MF or PV, or children under 12 with GVHD.

Side effects

The most common side effects of ruxolitinib in adults with MF and PV are:

• low platelet counts
• low red blood cell counts
• bruising
• dizziness
• headache
• diarrhea.

The most common side effects of ruxolitinib in people with aGVHD are:

• low red blood cell counts
• low platelet counts
• low white blood cell counts
• infections
• swelling.

The most common side effects of ruxolitinib in people with cGVHD are:

• low red blood cell counts
• low platelet counts
• infections, including viral infections.

Serious side effects and warnings

Ruxolitinib (either oral or topical) can cause the following serious side effects:

• Low blood cell counts. Ruxolitinib may cause low platelet counts (thrombocytopenia), low red blood cell counts (anemia), and low white blood cell counts (neutropenia). If you develop bleeding, stop ruxolitinib and call your healthcare provider. Your healthcare provider will do a blood test to check your blood cell counts before you start ruxolitinib and regularly during your treatment with ruxolitinib. Tell your healthcare provider right away if you develop or have worsening of any of these symptoms:
  • unusual bleeding
  • bruising
  • tiredness
  • shortness of breath
  • fever.
• Serious infections. Ruxolitinib belongs to a class of medicines called Janus kinase (JAK) inhibitors. JAK inhibitors are medicines that affect your immune system. JAK inhibitors can lower the ability of your immune system to fight infections. Some people have had serious infections while taking oral JAK inhibitors, including tuberculosis (TB), and infections caused by bacteria, fungi, or viruses that can spread throughout the body. Some people have been hospitalized or died from these infections. Some people have had serious infections of their lungs while using ruxolitinib cream. You may be at risk for developing a serious infection during treatment with ruxolitinib. Tell your healthcare provider if you develop any of the following symptoms of infection:
  • chills
  • aches
  • fever
  • nausea
  • vomiting
  • weakness
  • painful skin rash or blisters.
• Cancer. Some people have had certain types of non-melanoma skin cancers during treatment with ruxolitinib. Your healthcare provider will regularly check your skin during your treatment with ruxolitinib. Tell your healthcare provider if you develop any new or changing skin lesions during treatment with ruxolitinib.
• Cholesterol increases. You may have changes in your blood cholesterol levels during treatment with ruxolitinib. Your healthcare provider will do blood tests to check your cholesterol levels about every 8 to 12 weeks after you start taking ruxolitinib, and as needed.
• Increased risk of major cardiovascular events. Increased risk of major cardiovascular events such as heart attack, stroke, or death has occurred in people 50 years of age and older who have at least 1 heart disease (cardiovascular) risk factor and are taking oral JAK inhibitors, especially in current or past smokers. Get emergency help right away if you have any symptoms of a heart attack or stroke while taking ruxolitinib, including:
  • discomfort in the center of your chest that lasts for more than a few minutes, or that goes away and comes back
  • severe tightness, pain, pressure, or heaviness in your chest, throat, neck, or jaw
  • pain or discomfort in your arms, back, neck, jaw, or stomach
  • shortness of breath with or without chest discomfort
  • breaking out in a cold sweat
  • nausea or vomiting
  • feeling lightheaded
  • weakness in one part or on one side of your body
  • slurred speech.
• Increased risk of blood clots. Blood clots in the veins of your legs (deep vein thrombosis, DVT) or lungs (pulmonary embolism, PE) have happened in people taking another JAK inhibitor for rheumatoid arthritis and may be life-threatening. Tell your healthcare provider right away if you have any signs and symptoms of blood clots during treatment with ruxolitinib, including:
  • swelling, pain, or tenderness in one or both legs
  • sudden, unexplained chest or upper back pain
  • shortness of breath or difficulty breathing.
• Increased risk of death due to any reason (all causes). Increased risk of death has occurred in people 50 years of age and older who have at least 1 heart disease (cardiovascular) risk factor and are taking an oral JAK inhibitor, such as ruxolitinib.
• Possible increased risk of new (secondary) cancers. People who take another JAK inhibitor for rheumatoid arthritis have an increased risk of new (secondary) cancers, including lymphoma and other cancers. People who smoke or who smoked in the past have an added risk of new cancers.

These are not all the possible side effects of ruxolitinib. Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects to Incyte Corporation at 1-855-463-3463.

Related/similar drugs

Before taking

Before taking oral ruxolitinib, tell your healthcare provider about all of your medical conditions, including if you:

• have an infection
• have or have had low white or red blood cell counts
• have or had tuberculosis (TB), or have been in close contact with someone who has TB
• have had shingles (herpes zoster)
• have or had hepatitis B
• have or have had liver problems
• have or have had kidney problems or are on dialysis. If you are on dialysis, ruxolitinib should be taken after your dialysis.
• have a high level of fat in your blood (high blood cholesterol or triglycerides)
• have had cancer in the past
• are a current or past smoker
• have had a blood clot, heart attack, other heart problems or stroke
• are pregnant or plan to become pregnant. It is not known if ruxolitinib will harm your unborn baby.
• are breastfeeding or plan to breastfeed. It is not known if ruxolitinib passes into your breast milk. Do not breastfeed during treatment with ruxolitinib and for 2 weeks after the final dose.

How should I use ruxolitinib?

Take ruxolitinib exactly as your healthcare provider tells you. Do not change your dose or stop taking this medicine without first talking to your healthcare provider.

• Ruxolitinib is usually taken 2 times a day.
• You can take ruxolitinib with or without food.
• It may also be given through certain nasogastric tubes.

Tell your healthcare provider if you cannot take ruxolitinib by mouth. Your healthcare provider will decide if you can take it through a nasogastric tube.

• Ask your healthcare provider to give you specific instructions on how to properly take ruxolitinib through a nasogastric tube.

You will have regular blood tests during your treatment with ruxolitinib. Based on the results of your blood tests, your healthcare provider may change your dose of this medicine or stop your treatment.

Dosing information

Oral ruxolitinib dose for myelofibrosis

Dosage is based on the patient’s baseline platelet count

• Greater than 200 x 10⁹/L: 20 mg twice daily
• 100 x 109/L to 200 x 10⁹/L: 15 mg twice daily
• 50 x 109/L to less than 100 x 10⁹/L: 5 mg twice daily.

Monitor complete blood counts every 2 to 4 weeks until doses are stabilized, and then as clinically indicated. Modify or interrupt dosing for thrombocytopenia.

Oral ruxolitinib dose for polycythemia vera

• Starting dose: 10 mg twice daily.

Oral ruxolitinib dose for acute graft-versus-host-disease (aGVHD)

• Starting dose: 5 mg twice daily.

Oral ruxolitinib dose for chronic graft-versus-host disease (cGVHD)

• Starting dose: 10 mg twice daily.

What happens if I miss a dose?

If you miss a dose of ruxolitinib, take your next dose at your regular time. Do not take 2 doses at the same time.

What happens if I take too much?

If you take too much ruxolitinib, call your healthcare provider or go to the nearest hospital emergency room right away.

What other drugs will affect ruxolitinib?

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. Taking ruxolitinib with certain other medicines may affect how ruxolitinib works. Know the medicines you take. Keep a list of them to show your healthcare provider and pharmacist when you get a new medicine.

Storage

Store ruxolitinib tablets at room temperature, 68°F to 77°F (20°C to 25°C).

Keep out of the reach of children.

Ingredients

Active ingredient: ruxolitinib phosphate

Inactive ingredients: microcrystalline cellulose, lactose monohydrate, magnesium stearate, colloidal silicon dioxide, sodium starch glycolate, povidone, and hydroxypropyl cellulose.

Ruxolitinib is available as 5 mg, 10 mg, 15 mg, 20 mg, and 25 mg tablets.

Who makes ruxolitinib?

Oral ruxolitinib is made by Incyte Corporation under the brand Jakafi. Incyte is located in Wilmington, DE 19803.

Frequently asked questions

• What are the most common skin conditions? (with photos)

Further information

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

Medical Disclaimer