Pacritinib is a new targeted drug for the treatment of bone marrow fibrosis with severe thrombocytopenia, and its management of side effects such as bone marrow suppression, bleeding risk, and cardiac toxicity should be given special attention. The following explains the precautions from three aspects: medication monitoring, dosage adjustment, and special populations.

1. Side effect monitoring and management

(1) Bone marrow suppression: Regular monitoring of whole blood cell count. In case of grade 3 or above anemia or thrombocytopenia, medication should be suspended and blood transfusion support should be considered.

(2) Bleeding risk: Avoid co administration of anticoagulant drugs and discontinue medication for at least 7 days before surgery. When bleeding symptoms such as nosebleeds and bruising occur, seek medical attention immediately.

(3) Cardiotoxicity: Evaluate electrocardiogram before medication and monitor QT interval prolongation symptoms (dizziness, palpitations) during treatment.

Principle of dose adjustment

(1) Liver dysfunction: Moderate damage (Child Pugh B grade) reduced by 50%, severe damage (Child Pugh C grade) prohibited.

(2) Drug interactions: Avoid using potent CYP3A4 inhibitors/inducers in combination, and adjust the dosage when necessary.

3. Medication for special populations

(1) Pregnancy: It has embryonic toxicity, and women of childbearing age should take effective contraceptive measures from the time of medication until one month after discontinuation.

(2) Breastfeeding period: Medication may be secreted with breast milk. Breastfeeding is prohibited during treatment and for 2 weeks after discontinuation of medication.

(3) Elderly people: Patients aged 65 and above are more prone to anemia and need to increase the frequency of blood routine monitoring.