Anagrelide is a FDA-approved drug for the treatment of essential thrombocythemia. It is originally identified as a potential inhibitor of platelet aggregation. Anagrelide selectively affects thrombocytes while shows no significant effect on white blood cells, erythrocytes, or coagulation. Anagrelide is a potent inotropic agent for dogs with remarkable vasodilatory activity. Additionally, anagrelide can reduce renal blood flow. Furthermore, anagrelide has shown to play roles in other chronic myeloproliferative disorders, such as polycythemia vera, chronic myeloid leukemia and agnogenic myeloid metaplasia. Anagrelide has some side effects involving headache, diarrhea, edema, palpitations, and abdominal pain.