Carbamazepine thrombocytopenia with

Some 15 cases of thrombocytopenia, reversible after withdrawal of carbamazepine, have been published (SED-13, 147) (41,42). There have also been single case reports of reticulocytosis (SED-13,147) (43), leukopenia with thrombocytopenia with Henoch-Schonlein purpura (SEDA-18,63), hemolytic anemia, and pure red cell aplasia (SED-13,147) (44). 

Because of the potential for hematological and hepatic toxicity, carbamazepine should not be administered to patients with liver disease or thrombocytopenia or to those at risk for agranulocytosis. For this reason, carbamazepine is strictly contraindicated in patients receiving clozapine. Because of reports of teratogenicity, including increased risks of spina bifida (Rosa 1991), microcephaly (Bertol-lini et al. 1987), and craniofacial defects (Jones et al. 1989), carbamazepine is relatively contraindicated in pregnant women. Pretreatment evaluation should include a complete blood count and determination of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels. 

Tohen M, Castillo J, Cole JO, Miller MG, de los Heros R, Farrer RJ. Thrombocytopenia associated with carbamazepine a case series. J Clin Psychiatry 1991 52(12) 496-8. 

The therapeutic concentration range for optimal pharmacological effect of carbamazepine is 4 to 12p,g/mL. Toxicity associated with excessive carbamazepine ingestion occurs at plasma concentrations in excess of 15p.g/mL and is characterized by symptoms of blurred vision, paresthesia, nystagmus, ataxia, drowsiness, and diplopia. Side effects unrelated to plasma concentration include development of an urticarial rash, which usually disappears on discontinuation of the drug, and hematological depression (leukopenia, thrombocytopenia, and aplastic anemia). 

Thrombocytopenia and anemia are relatively rare events that usually respond to discontinuation of the offending drug. Leukopenia is the most common hematologic side effect. An incidence as high as 10% has been reported. Leukopenia usually is transient, even when the drug is continued, and may be due to a redistribution of white blood cells (WBCs) rather than a decrease in their production. In about 2% of patients, the leukopenia is persistent, but even patients with WBC counts of3000/mm or less do not seem to have an increased incidence of infection. A clinical guide is to continue carbamazepine therapy unless the WBC count drops to less than 2500/mm and the absolute neutrophil count drops to less than 1000/mm. " ... 

Carbamazepine has a moderate anticholinergic action that may cause symptoms of dry mouth and constipation. CNS effects include somnolence, ataxia, diplopia, loss of accommodation, dizziness, and headache, which are most prominent with overdosage. Erythroderma, photosensitivity, and skin rashes may also be seen, and, rarely, Stevens-Johnson syndrome or systemic lupus-like syndrome also occur. The drug also has other serious adverse effects, such as suppression of ventricular automaticity, and, rarely, blood dyscrasias (e.g.. agranulocytosis, leukopenia, thrombocytopenia, and aplastic anemia). Due to hepatic metabolism, hepatocellular and cholestatic jaundice may also be seen. 

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