Yerby M S, Friel P N, McCormick K
Oregon Comprehensive Epilepsy Program, Portland 97210.
Neurology. 1992 Apr;42(4 Suppl 5):12-6.
A significant proportion of women with epilepsy have an increase in their seizure frequency during pregnancy. Multiple factors may be involved in this phenomenon, but changes in antiepileptic drug (AED) concentration appear to be the most significant. AED concentration declines as pregnancy progresses, due primarily to dynamic changes in plasma protein binding. Total concentrations of all first-line AEDs (carbamazepine, phenytoin, phenobarbital, and valproic acid) fall significantly during pregnancy, compared to baseline. Free or unbound drug concentrations, however, fall significantly only for phenobarbital. Valproate free concentrations actually increase by 25% by delivery. Women taking carbamazepine, phenytoin, or valproate may be relatively protected by adequate free concentrations of these compounds. When managing pregnant women with epilepsy, measurement of free AED concentrations and appropriate dose adjustment to maintain therapeutic ranges will permit more effective clinical management than using total concentration values.
相当一部分癫痫女性在孕期癫痫发作频率会增加。这一现象可能涉及多种因素，但抗癫痫药物（AED）浓度的变化似乎最为关键。随着孕期进展，AED浓度会下降，这主要是由于血浆蛋白结合的动态变化所致。与基线相比，所有一线AED（卡马西平、苯妥英、苯巴比妥和丙戊酸）的总浓度在孕期均显著下降。然而，只有苯巴比妥的游离或未结合药物浓度会显著下降。丙戊酸的游离浓度在分娩时实际上会增加25%。服用卡马西平、苯妥英或丙戊酸的女性可能会因这些化合物足够的游离浓度而受到相对保护。在管理癫痫孕妇时，测量游离AED浓度并进行适当的剂量调整以维持治疗范围，将比使用总浓度值实现更有效的临床管理。
