卡马西平的疗效和副反应

目的验证卡马西平的疗效和副反应。方法前瞻性观察近5年以来住本院以后服用卡马西平治疗的男性患者，共60例。结果卡马西平对癫瘸和情感障碍的疗效是确切的，并对情感障碍的复发有很好的预防作用；对偏头痛、室早、冲动、攻击行为有一定的疗效，对迟发性运动障碍的疗效不明显。本研究未遇到尿崩症患者，疗效未得到验证。结论卡马西平的作用广泛，疗效肯定，但是使用过程中除出现一般副反应以外偶尔出现严重的致命性的副反应，需要慎重使用。     

Comparison of Steady-State Blood Levels of Two Carbamazepine Formulations

The steady-state plasma level produced by brand-name carbamazepine (CBZ) (Tegretol, Ciba-Geigy) was compared with a generic formulation (Parke-Davis) in 10 subjects with partial epilepsy in a randomized, double-blind, cross-over clinical trial. In addition, seizure frequency and clinical and laboratory signs of toxicity were evaluated. Our results failed to show any difference in CBZ blood levels, seizure frequency, or clinical or laboratory signs of toxicity in patients receiving either the brand-name or generic formulation.     

Effects of the Removal of Phenytoin, Carbamazepine, and Valproate on the Electroencephalogram

We report the EEG changes that occurred on discontinuance of phenytoin (PHT), carbamazepine (CBZ), and valproate (VPA) in patients with active epilepsy. Discontinuation of CBZ was associated with an increase in mean frequency of dominant rhythm and reduction in amount of slow activity. Patients who had a marked increase in seizures on discontinuation of an antiepileptic drug had a slower mean dominant rhythm at baseline than did patients who did not have an increase in seizures. Subsequent EEGs, during and at the end of drug reduction, showed an increase in bursts of interictal epileptiform activity (IEA) and in slow activity in patients who had a marked increase in seizures. The amount of slow activity and IEA did not alter in patients who did not have an increase in seizures. No patients developed photosensitivity.     

Carbamazepine coadministration with an oral contraceptive: effects on steroid pharmacokinetics, ovulation, and bleeding

Purpose: Antiepileptic drugs (AEDs) are widely used in reproductive‐age women. The AED carbamazepine (CBZ) induces the hepatic cytochrome P450 system, thereby accelerating hormone metabolism. We sought to assess the pharmacodynamic effects of CBZ on breakthrough bleeding and ovulation during oral contraceptive (OC) use. Methods: A double‐blind, randomized, crossover study of healthy women ages 18–35 years. Participants took an OC containing 20 μg ethinyl estradiol (EE) and 100 μg levonorgestrel (LNG) for 4 months. Concurrently, participants took 600 mg CBZ or a matching placebo for 2 months each, administered in random order. During the second month of CBZ or placebo, we measured EE and LNG levels 12 times over 24 h, ovarian follicular diameters with eight biweekly vaginal ultrasounds, weekly progesterone levels, and bleeding (using a diary). Key Findings: We enrolled 25 women; 10 completed the study. Five women discontinued because of reversible CBZ side effects. Mean area under the curve (AUC) measurements were lower during CBZ use compared to placebo for EE (1,778 vs. 986 pg*h/ml, p < 0.001) and LNG (24.8 vs. 13.8 pg*h/ml, p = 0.04). Ovulation occurred in 5 of 10 CBZ cycles compared to 1 of 10 placebo cycles (p = 0.06). Three or more days of breakthrough bleeding occurred during 8 of the 10 CBZ cycles compared to 2 of the 10 placebo cycles (p = 0.07). Significance: A commonly used dose of CBZ decreased levels of contraceptive steroids, increased breakthrough bleeding, and permitted ovulation during use of a low‐dose OC. Women treated with CBZ are not adequately protected from pregnancy by low‐dose OCs.     

Diurnal fluctuations in free and total steady-state plasma levels of carbamazepine and correlation with intermittent side effects

The relationship between diurnal fluctuations in free (unbound) and total plasma carbamazepine levels and the appearance of intermittent side effects was investigated in nine epileptic patients receiving chronic therapy with carbamazepine, alone or in combination with phenobarbital. On a three-times-daily or four-times-daily dosing schedule, both total and free carbamazepine levels fluctuated considerably (on an average, 41 and 45%, respectively, around the mean). Side effects (particularly diplopia and nystagmus) were observed in five patients and showed an intermittent pattern in four. Side effects were never found at total carbamazepine levels less than 34 mumol/L but invariably appeared at levels greater than 38 mumol/L. At levels between 34 and 38 mumol/L adverse effects were inconsistently observed. The correlation between plasma carbamazepine levels and manifestations of toxicity was slightly stronger when free rather than total levels were considered. Side effects were always apparent at free levels greater than 7.2 mumol/L. These data underline the limitations of relying on a single drug level determination during the monitoring of carbamazepine therapy and emphasize the necessity of carefully adjusting the dosing schedule, to minimize the appearance of intermittent adverse effects.     

Discontinuation of Phenytoin, Carbamazepine, and Valproate in Patients with Active Epilepsy

The effects of discontinuing individual antiepileptic drugs (AEDs) in patients with active epilepsy who are receiving combination therapy have not been studied systematically. We report a double-blind, prospective study of discontinuation of phenytoin (PHT), carbamazepine (CBZ), and valproate (VPA) in 70 patients with chronic active epilepsy. Each drug discontinuation was randomized to one of two relatively fast rates of reduction, and a control group of 25 patients continued with stable therapy. Patients who had CBZ removed had a significant increase in seizures that was maintained for 4 weeks after the end of drug reduction, and 10 of these 23 patients had to restart therapy with CBZ. There was no significant change in seizure numbers in the other groups. Two patients discontinued from VPA had to restart the drug; none had to restart PHT. The optimal rates of reduction of CBZ remain uncertain. There was no evidence for a clinically or temporally distinct burst of "discontinuation seizures" in any group. Any marked increase in seizures always resolved on reintroduction of the discontinued drug.