No proven relationship of carbamazepine therapy to blood dyscrasias

Phenobarbital-associated bone marrow aplasia: a case report and review of the literature

We report on a 22-year-old female who developed aplastic anemia after administration of phenobarbital for 6 years. Being refractory to steroid and anti-lymphocyte serum, the patient received allogeneic stem cell transplantation, achieving complete remission. We discuss here the potential mechanisms by which phenobarbital and other anti-epileptic drugs can cause aplastic anemia and review the literature for previous case reports and epidemiological studies.

A review of carbamazepine's hematologic reactions and monitoring recommendations

Early case reports of fatal hematologic effects attributed to carbamazepine (CBZ) resulted in extensive monitoring recommendations by the manufacturer. The rarity of blood dyscrasias led many authors to question the manufacturer's guidelines. Thus the manufacturer removed specific monitoring guidelines, allowing physicians to monitor CBZ using their clinical judgment. This article reviews case reports and studies of CBZ's hematologic effects. Due to their rapid onset, daily laboratory checks would be necessary to monitor for aplastic anemia, agranulocytosis, and thrombocytopenia. These adverse effects are best monitored by informing patients and physicians to carefully watch for signs and symptoms. Leukopenia develops more slowly, occurring in approximately 12 percent of children and 7 percent of adults. Its onset is typically within the first three months of treatment, with patients at risk having a low or low-normal pretreatment white blood cell (WBC) count. Leukopenia often reverses, even if CBZ is continued. Based upon our review of the literature, we recommend monitoring of those high-risk patients during the first three months of treatment with the frequency being determined by results of each laboratory value. WBC counts less than 3000/mm3 or neutrophil counts below 1000/mm3 warrant a decrease in dose with frequent monitoring or CBZ discontinuation, if necessary.

A retrospective study of compliance with recommended hematologic monitoring of carbamazepine

Early case reports of fatal hematologic effects associated with carbamazepine (CBZ) resulted in manufacturer recommendations for extensive laboratory monitoring. Several alternative monitoring protocols have been published, indicating disagreement with those recommendations. The manufacturer has removed specific monitoring guidelines allowing physicians to monitor CBZ during treatment based on their clinical judgment. This study was designed to determine the frequency of CBZ hematologic monitoring in one academic setting. Data on complete blood counts (CBCs) were retrospectively obtained and were compared with 1975-88 Physicians' Desk Reference recommendations for weekly CBCs during the first three months of treatment. Eighty-three patients were identified: 32 psychiatry, 37 neurology, and 14 from other clinics. Only one patient met guidelines for monitoring during the entire first three months of treatment. Comparisons between clinics demonstrated no statistically significant differences in monitoring rates. Prospective studies in academic and private practice settings are needed to provide more information on actual monitoring practices. Due to the removal of specific manufacturer recommendations, a standard approach is needed to establish consistent and adequate monitoring and to provide legal support to prescribers.

Agranulocytosis associated with carbamazepine, and a positive reaction with anti-lymphoid leukaemia antiserum during recovery

Carbamazepine is a valuable drug in the treatment of trigeminal neuralgia and temporal lobe epilepsy. Rarely agranulocytosis has been described associated with its use but in this further non-fatal case a new finding of a positive reaction with anti-lymphoid leukaemia anti-serum was seen during the recovery phase. A brief review of 18 cases in the literature is provided and it is noted that 94% of reported cases are over the age of 45 years. The significance of the haematological finding is discussed.