To explore the influencing factors for serum concentration of oxcarbazepine active metabolite 10, 11-dihydro-10-hydroxyl carbazepine (MHD), and the effecacy of clinical pharmacists' intervention in administration scheme through serum concentration monitoring.

A total of 96 patients with epilepsy who were treated with oxcarbazepine or oxcarbazepine combined with other drugs in our hospital from August 2017 to December 2021 were selected. Blood samples with monitored MHD concentration during treatment in our hospital in these patients were used as the research objects. Univariate analysis and multivariate linear regression analysis were used to analyze the influence of gender, age, body weight, daily dose of oxcarbamide, liver and kidney functions and medication in serum MHD concentration. For patients with substandard serum MHD concentration or ineffective treatment, clinical pharmacists would intervene the medication regimen and lifestyle; the differences of compliance rate of serum MHD concentration and incidence of adverse reactions were compared between the intervention group and non-intervention group.

A total of 190 blood samples were collected from these 96 patients. There was significant difference in serum MHD concentration among samples with different daily doses of oxcarbazepine, different creatinine clearance rate (Ccr), and different medications (P<0.05). Correlation analysis showed that daily dose of oxcarbazepine was positively correlated with serum MHD concentration (r=0.655, P<0.001). Multivariate linear regression analysis showed that daily dose of oxcarbazepine (95%CI: 0.009-0.014, P<0.001), Ccr (95%CI: -0.037-0.007, P=0.005), and combined use of oxcarbazepine with lamotrigine (95%CI: 0.526-8.790, P=0.027) or atorvastatin (95%CI: 0.213-5.168, P=0.033) were independent influencing factors for serum MHD concentration. For patients whose blood concentration was monitored for the first time, the serum MHD concentration in patients with somnolence and/or dizziness (10.9 [6.7, 14.0] μg/mL) was significantly higher than that in patients without somnolence and/or dizziness (7.5 [5.2, 9.4] μg/mL, P<0.05). The compliance rate of serum MHD in the intervention group (83/85[97.6%]) was statistically higher than that in the non-intervention group (95/105[90.5%]), and the incidence of adverse reactions (11/85[12.9%]) was statistically lower than that in the non-intervention group (28/105[26.7%], P<0.05).

The serum MHD concentration is affected by daily dose of oxcarbamide, Ccr, and combined use of oxcarbazepine with lamotrigine or atorvastatin. Clinical pharmacists should be encouraged to participate in clinical drug treatment to achieve better effectiveness and safety of drug treatment.

Oxcarbazepine; 10,11-dihydro-10-hydroxyl carbazepine; Serum concentration; Factor; Intervention