International Journal of Medical Discoveries

Background: Carbamazepine and phenytoin are the mainstays of epilepsy treatment. The antiepileptics depend on the patient’s condition and ensure seizure control without causing any adverse effects, such as anaemia. Anaemia is not a lifethreatening condition; however, it disrupts the outcomes of epilepsy patients.
Purpose: The main purpose of the study was to investigate and associate the use of carbamazepine and phenytoin in adult epilepsy patients and the anaemia incidence.
Materials and Methods: A retrospective cohort study was performed between January 2020 and February 2023 at King Saud University Medical City. The study involved adult patients with epilepsy treated with carbamazepine or phenytoin independently or in addition to the Antiepileptic drug regimen. Patients 18 years or older were eligible for the study. Patients with a history of anaemia before starting carbamazepine or phenytoin, or any comorbidities besides epilepsy, were excluded as they can disrupt blood measurements. The primary outcome was the incidence of anaemia as per WHO criteria. The secondary outcomes highlighted the incidence of anaemia and types of epilepsy, folic acid supplements, and the drug serum level. The study employed the Shapiro Wilk test to measure data normality, the Mann–Whitney U test to link nonnormally distributed variables, Pearson’s Chi-square and Fisher’s Exact tests to examine categorical variables, and Pearson’s correlation test. A significance level set at p < 0.05.
Results: A total of 724 participants, aged 37 (27-48) years, were treated with carbamazepine, whereas 300 participants, aged 46 (33-55) years, were treated with phenytoin. The results of multivariable logistic regression analyses aligned with the univariate analyses regarding female subjects treated with carbamazepine. The females treated with carbamazepine had 2.33 times (95% CI: 1.39-3.87) (p =0.001) was possible to have anaemia than those treated with phenytoin. A significant correlation was found between phenytoin plasma concentration and the incidence of anaemia in female subjects (p =0.002). The most common type of anaemia based on Mean Corpuscular Volume was normocytic anaemia, and the highest occurrence of anaemia was mild to moderate in both groups.
Conclusion: The most common antiepileptic drugs are carbamazepine and phenytoin; however, they pose some side effects, including anaemia, particularly normocytic anaemia. The study is beneficial in the healthcare system, highlighting the importance of drug therapy in patients with epilepsy.