Momelotinib is a targeted therapy used for the treatment of intermediate/high-risk myelofibrosis with anemia. Understanding its common side effects, mastering management strategies, and proper storage can improve treatment tolerability and safety.
I. What are the common side effects?
1. Thrombocytopenia and bleeding tendency
(1) Approximately 20% of patients experience platelet counts below 50×10⁹/L, presenting as unusual bruising, gum bleeding, or black stools.
(2) Severe cases may increase the risk of internal bleeding.
2. Neutropenia
About 2% of patients develop severe neutropenia, predisposing them to bacterial or viral infections, manifested as recurrent fever and sore throat.
3. Increased risk of infection
(1) Approximately 38% of patients experience various types of infections (bacterial, viral, including COVID-19), with serious infections accounting for 13%.
(2) Watch for signs such as fever, cough, or diarrhea.
4. Elevated liver enzymes and bilirubin
23% and 24% of patients have elevated ALT and AST, respectively, and 16% have elevated total bilirubin, but these are usually mild (grade 1-2) and reversible upon discontinuation.
5. Other common reactions
More than 20% of patients report diarrhea, dizziness, nausea, and fatigue; some patients experience abdominal pain, rash, limb pain, or blurred vision.
II. How to manage side effects
1. Management of thrombocytopenia
(1) Depending on platelet count, the doctor will reduce the daily dose by 50 mg or temporarily discontinue the drug, and resume at a lower dose once counts return to a safe level.
(2) Avoid using medications that affect blood coagulation, such as aspirin or ibuprofen, in daily life.
2. Prevention and control of infections
(1) Active infections must be ruled out before treatment. During treatment, wash hands frequently, wear a mask, and seek immediate medical attention if fever or shortness of breath occurs.
(2) Patients with chronic hepatitis B should be monitored for viral reactivation.
3. Management of abnormal liver enzymes
(1) Monitor liver function monthly for at least 6 months after starting treatment.
(2) If transaminases exceed 5 times the upper limit of normal or total bilirubin exceeds 2 times, the drug should be interrupted, and resumed at a reduced dose after recovery.
4. Management of diarrhea and nausea
(1) For diarrhea, replenish fluids and electrolytes, and choose low-fiber, easily digestible foods.
(2) For nausea, eat small, frequent meals and avoid taking the drug on an empty stomach. Inform your doctor if symptoms are severe.
5. Alleviating fatigue
(1) Ensure 7-8 hours of nighttime sleep and arrange 20-30 minutes of short rest during the day.
(2) Moderate low-intensity activities such as walking can help maintain physical strength.
III. Storage requirements
1. Temperature and container
(1) Store at room temperature between 20-25°C; brief excursions between 15-30°C are permitted.
(2) Keep in the original bottle, and tighten the cap immediately after each use to prevent moisture absorption.
2. Moisture prevention and dryness
(1) Do not discard the desiccant in the bottle; it absorbs excess moisture.
(2) Do not transfer to other containers, and avoid storing in humid environments such as bathrooms or kitchens.
IV. Indications for emergency medical attention
Seek immediate medical attention if any of the following occurs: chest pain, unilateral limb swelling, or sudden difficulty breathing (indicating thrombosis); progressive rash with blisters or skin peeling (indicating severe skin reaction); hematemesis or black stools (indicating gastrointestinal bleeding).
