Takeoka M, Krishnamoorthy K S, Soman T B, Caviness V S
Department of Neurology, Massachusetts General Hospital, Boston 02114, USA.
J Child Neurol. 1998 Nov;13(11):537-40. doi: 10.1177/088307389801301102.
In comparison with phenytoin preparations, which have a pH value of 11, fosphenytoin, a phosphorylated prodrug of phenytoin, has a pH value of only 8.6, which decreases the risk of cardiovascular and cutaneous side effects. The near-neutral pH value of fosphenytoin allows effective intravenous or intramuscular administration. A 1-mg phenytoin equivalent (PE) of fosphenytoin is converted to 1 mg of phenytoin in adults. We describe four infants whose seizures were treated with intravenous fosphenytoin. We had difficulty maintaining therapeutic serum phenytoin levels of 10 to 20 microg/mL on doses of 5 to 8 mgPE/kg/day, and many bolus doses of 5 to 10 mgPE/kg or maintenance doses of more than 10 mgPE/kg/day were given. Despite increased doses in three out of the four patients, a therapeutic serum phenytoin level was not maintained. From our experience, careful and individual dosing of fosphenytoin in this age group can be considered.
与pH值为11的苯妥英制剂相比，苯妥英的磷酸化前体药物磷苯妥英的pH值仅为8.6，这降低了心血管和皮肤副作用的风险。磷苯妥英接近中性的pH值允许进行有效的静脉内或肌内给药。在成人中，1毫克磷苯妥英的苯妥英等效物（PE）可转化为1毫克苯妥英。我们描述了4例接受静脉注射磷苯妥英治疗癫痫发作的婴儿。在5至8毫克PE/千克/天的剂量下，我们难以将苯妥英血清治疗水平维持在10至20微克/毫升，并且给予了许多5至10毫克PE/千克的推注剂量或超过10毫克PE/千克/天的维持剂量。尽管4名患者中有3名增加了剂量，但仍未维持苯妥英血清治疗水平。根据我们的经验，对于该年龄组的磷苯妥英可以考虑进行仔细的个体化给药。
