Pruritus is the medical term for skin itching. Some patients with MPNs have skin itching that can be intermittent and predictable, intermittent and unpredictable, or even constant. The most common predictable trigger for itching is exposure to warm or hot water during showering or bathing. Some drugs used in the treatment of CML (e.g., imatinib, nilotinib, dasatinib) can cause skin itching, particularly when therapy is first started or changed. The medical cause for the itching in patients with MPNs has not been fully identified.
There is no single, best treatment for pruritus and therapy typically needs to be individualized. Simple measures like using cooler water when bathing are often effective and sufficient for many patients. Itching due to CML drugs usually resolves on its own, but care by experienced dermatologists and treatment with topical lotions can provide significant relief. Patients with severe or unremitting itching can benefit from exposure to ultraviolet light (natural or under the direction of dermatologist). Ruxolitinib, a drug approved for use in polycythemia vera and myelofibrosis, has been found to be very effective in relieving pruritus for many patients. While sometimes patients take antihistamine medications such as Benadryl, Claritin, and Allegra, but these infrequently provide relief.