This medication may interact with the following medications:

-antiviral medicines for HIV or AIDS
-apalutamide
-certain medicines for fungal infections like fluconazole, itraconazole, ketoconazole, posaconazole, and voriconazole
-certain antibiotics like clarithromycin, chloramphenicol, telithromycin, and dalfopristin; quinupristin
-certain medicines for seizures like carbamazepine, phenobarbital, fosphenytoin/phenytoin, and primidone
-conivaptan
-enzalutamide
-grapefruit juice
-idelalisib
-lumacaftor; ivacaftor
-mifepristone
-mitotane
-nefazodone
-ribociclib
-rifampin
-St. John''s wort

They need to know if you have any of these conditions:

-cancer of the skin
-hepatitis
-high cholesterol
-infection (especially a virus infection such as chickenpox, cold sores, or herpes)
-kidney disease
-liver disease
-low blood counts, like low white cell, platelet, or red cell counts
-an unusual or allergic reaction to ruxolitinib, other medicines, foods, dyes, or preservatives
-pregnant or trying to get pregnant
-breast-feeding

You may need blood work done while you are taking this medicine.

Call your doctor or health care professional for advice if you get a fever, chills or sore throat, or other symptoms of a cold or flu. Do not treat yourself. This drug decreases your body''s ability to fight infections. Try to avoid being around people who are sick.

This medicine may increase your risk to bruise or bleed. Call your doctor or health care professional if you notice any unusual bleeding.

In some patients, this medicine may cause a serious brain infection that may cause death. If you have any problems seeing, thinking, speaking, walking, or standing, tell your doctor right away. If you cannot reach your doctor, urgently seek other source of medical care.

Talk to your doctor about your risk of cancer. You may be more at risk for certain types of cancers if you take this medicine.

Do not breast-feed an infant while taking this medicine or for at least 2 weeks after stopping it.

Keep out of the reach of children.

Store between 20 and 25 degrees C (68 and 77 degrees F). Throw away any unused medicine after the expiration date.