Generic name: pacritinib [ pa-KRI-ti-nib ]
Drug class: Multikinase inhibitors
Medically reviewed by Drugs.com. Last updated on Dec 18, 2022.
Uses for pacritinib
Pacritinib is used to treat intermediate or high-risk myelofibrosis, including primary myelofibrosis, post-polycythemia vera myelofibrosis, and post-essential thrombocythemia myelofibrosis. Myelofibrosis is a life-threatening bone marrow problem which is manifested by the following symptoms: enlarged spleen (splenomegaly), severe itching, fever, night sweats, weight loss, bone pain, or unusual tiredness or weakness.
Pacritinib is a kinase inhibitor that works on the immune system.
This medicine is available only with your doctor's prescription.
Before using pacritinib
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Appropriate studies have not been performed on the relationship of age to the effects of pacritinib in the pediatric population. Safety and efficacy have not been established.
Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of pacritinib in the elderly.
There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.
Interactions with Medicines
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
- St John's Wort
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Aripiprazole Lauroxil
- Arsenic Trioxide
- Inotuzumab Ozogamicin
- Sodium Phosphate
- Sodium Phosphate, Dibasic
- Sodium Phosphate, Monobasic
Interactions with Food/Tobacco/Alcohol
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following is usually not recommended, but may be unavoidable in some cases. If used together, your doctor may change the dose or how often you use this medicine, or give you special instructions about the use of food, alcohol, or tobacco.
- Grapefruit Juice
Other Medical Problems
The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:
- Cancer, history of or
- Diarrhea or
- Heart or blood vessel disease or
- Thrombocytopenia (low number of platelets)—Use with caution. May make these conditions worse.
- Infection—May decrease your body's ability to fight infection.
- Kidney disease or
- Liver disease—Use with caution. The effects may be increased because of slower removal of the medicine from the body.
- Smoker, current or past—May increase risk for serious side effects.
Proper use of pacritinib
Take this medicine only as directed by your doctor. Your dose depends on your platelet count and needs to be changed several times in order to find out what works best for you. Do not use more medicine, do not use it more often, and do not use it for a longer time than your doctor ordered.
This medicine comes with a patient information insert. Read and follow the instructions carefully. Ask your doctor if you have any questions.
Keep using this medicine for as long as your doctor has told you to. Do not change your dose or stop taking this medicine without first talking with your doctor.
Take this medicine with or without food.
Swallow the capsule whole. Do not open, break, or chew it. Take this medicine about the same time each day.
If you are using other kinase inhibitors, your doctor may adjust your dose or stop taking other kinase inhibitor medicines before you start treatment with pacritinib.
The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
- For oral dosage form (capsules):
- For myelofibrosis:
- Adults—200 milligrams (mg) 2 times a day, depending on your blood test results. Your doctor will adjust your dose as needed and tolerated.
- Children—Use and dose must be determined by your doctor.
- For myelofibrosis:
If you miss a dose of this medicine, skip the missed dose and go back to your regular dosing schedule. Do not double doses.
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.
Ask your healthcare professional how you should dispose of any medicine you do not use.
Precautions while using pacritinib
It is very important that your doctor check your progress at regular visits to make sure this medicine is working properly. Blood tests will be needed to check for unwanted effects.
Do not use this medicine together with clarithromycin (Biaxin®) and rifampin (Rifadin®).
Check with your doctor right away if you have any unusual bleeding or bruising, black, tarry stools, blood in the urine or stools, headache, dizziness, or weakness, pain, swelling, or discomfort in a joint, pinpoint red spots on your skin, unusual nosebleeds, or unusual vaginal bleeding that is heavier than normal. These may be signs of bleeding problems.
Pacritinib may cause diarrhea, nausea, or vomiting, and in some cases it can be severe. Do not take any medicine to treat diarrhea without first checking with your doctor. Diarrhea medicines may make the diarrhea worse or make it last longer. If you have any questions about this or if mild diarrhea, nausea, or vomiting continues, or gets worse, check with your doctor.
Pacritinib will lower the number of some types of blood cells in your body. Because of this, you may bleed or get infections more easily. To help with these problems, avoid being near people who are sick or have infections. Wash your hands often. Stay away from rough sports or other situations where you could be bruised, cut, or injured. Brush and floss your teeth gently. Be careful when using sharp objects, including razors and fingernail clippers.
Contact your doctor right away if you have any changes to your heart rhythm. You might feel dizzy or faint, or you might have a fast, pounding, or uneven heartbeat. Make sure your doctor knows if you had a heart rhythm problem, such as QT prolongation.
This medicine may increase your risk of serious heart or blood vessel problems, including heart attack or stroke. Call your doctor right away if you have chest pain or discomfort, confusion, difficulty in speaking, double vision, headache, inability to move arms, legs, or facial muscles, nausea, pain or discomfort in the arms, jaw, back, or neck, sweating, trouble breathing, or vomiting.
Check with your doctor right away if you have anxiety, chest pain, cough, dizziness, lightheadedness, or fainting, fast heartbeat, pain, redness, or swelling in the arm or leg, pains in the chest, groin, or legs, especially calves of the legs, severe headaches, sudden loss of coordination, sudden onset of slurred speech, sudden vision changes, or trouble breathing. These may be symptoms of serious blood clots (eg, deep vein thrombosis, pulmonary embolism, arterial thrombosis).
This medicine may increase your risk of cancer (eg, lymphoma, non-melanoma skin cancer). Tell your doctor right away if you have black, tarry stools, general feeling of illness, swollen glands, weight loss, yellow skin and eyes, persistent non-healing sore, reddish patch or irritated area, shiny bump, pink growth, or white, yellow or waxy scar-like area on the skin.
Your body's ability to fight infections may be reduced while you are using baricitinib. It is very important that you call your doctor at the first sign of an infection. Check with your doctor right away if you have a fever, chills, cough, flu-like symptoms, or unusual tiredness or weakness.
Some men who use this medicine have become infertile (unable to have children). Talk with your doctor before using this medicine if you plan to have children.
Make sure any doctor or dentist who treats you knows that you are using this medicine. You may need to stop using this medicine 7 days before having surgery or medical tests.
Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.
Side Effects of pacritinib
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
- Black, tarry stools
- bleeding gums
- bloating or swelling of the face, arms, hands, lower legs, or feet
- blood in the urine or stools
- body aches or pain
- ear congestion
- loss of voice
- pale skin
- pinpoint red spots on the skin
- rapid weight gain
- sore throat
- stuffy or runny nose
- tingling of the hands or feet
- trouble breathing
- unusual bleeding or bruising
- unusual tiredness or weakness
- unusual weight gain or loss
- Bloody eye
- lower back or side pain
- painful or difficult urination
- redness of the eye
- ulcers, sores, or white spots in the mouth
- unusual bleeding or bruising
Incidence not known
- Chest pain or discomfort
- coughing up blood
- difficulty in speaking
- double vision
- general feeling of illness
- inability to move the arms, legs, or facial muscles
- inability to speak
- increased menstrual flow or vaginal bleeding
- irregular heartbeat recurrent
- pain or discomfort in the arms, jaw, back, or neck
- persistent non-healing sore
- pink growth
- prolonged bleeding from cuts
- red or dark brown urine
- reddish patch or irritated area
- shiny bump
- slow speech
- swollen glands
- tenderness, pain, swelling, warmth, skin discoloration, and prominent superficial veins over the affected area
- weight loss
- white, yellow or waxy scar-like area
- yellow skin and eyes
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
- Bloody nose
- itching skin
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
More about pacritinib
- Check interactions
- Compare alternatives
- Side effects
- Dosage information
- During pregnancy
- Drug class: multikinase inhibitors
- En español
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