Aplastic anemia and agranulocytosis are extremely rare side effects of anticonvulsant therapy . Felbamate (not marketed in Canada) was reported to cause aplastic anemia at an annual rate of one/2000 patients. Chronic leukopenia has been reported with phenobarbital, phenytoin, valproic acid and, especially, carbamazepine . The leukopenia is generally mild, with leukocyte counts remaining above 2000/mm3 . In one study, 21% of patients treated with carbamazepine and 14% of patients on other anticonvulsants developed transient leukopenia . It is recommended that, if the absolute white blood cell count decreases to less than 1000/mm3, the bone marrow should be examined . Valproic acid may cause dose-dependent thrombocytopenia or increased bleeding time due to inhibition of platelet aggregation. Most clinicians recommend a decrease in the valproic acid dosage in response to platelet counts below 100,000/mm3. Your drugs could be so cheap – get Purchase Zyrtec at trusted foreign online pharmacy.
Lower folate levels and increased folate clearance are found in patients on phenytoin. Dermatological manifestations of folate deficiency include cheilitis, glossitis and mucosal ulceration. Folate supplementation can correct the anemia but may increase the seizure frequency. Megaloblastic anemia, secondary to folic acid deficiency, may complicate therapy with phenobarbital and primidone.