Treatment of essential thrombocythemia

Anagrelide is a platelet-reducing agent. Platelet aggregation is inhibited when higher than therapeutic doses are used. Anagrelide may become the first-line agent for essential thrombocythemia, especially in patients for whom other therapies (hydroxyurea and alpha-interferon) may be contraindicated.

The drug is metabolized in the liver and less than 1% of the dose appears unchanged in the urine; the plasma half-life of the drug is 1.3 hours.

Hypersensitivity to Anagrelide; Use with caution in patients of cardiovascular disease, renal insufficiency ( serum creatinine ＞2.0 mg/dl), and liver failure (liver function tests over 1.5 times normal).

C

Infant risk cannot be ruled out.

Palpitations, abdominal pain, edema, diarrhea, and headache are dose-related adverse effects. Use with caution in patients with cardiovascular disease.

Adults:
Initial: 0.5 mg 4 times daily or 1 mg twice daily.
Dose titration: Maintain initial dose for at least 1 week, then titrate to reduce and maintain platelet count <600,000/mm3 and ideally between 150,000/mm3 and 400,000/mm3; the dose must not be increased by >0.5 mg per day in any 1 week; maximum single dose: 2.5 mg; maximum daily dose: 10 mg