">Table 2. Pharmacokinetic parameters of Sincronil and Topamax.

Table 3. Bioequivalence of Topamax and Sincronil as evaluated with the ratio of the least squares means and the 90% geometric confidence interval (CI) of the AUC0-inf AUC0-t and Cmax.

cokinetic data for preparations containing 50 mg topira mate are reported, since in previous studies in healthy subjects, the dose of topiramate studied were 100 - 200 mg, possibly because the doses of the drug used for the treatment of epilepsy are larger than those used in migraine prevention [11-14]. Considering published data on topiramate pharmacokinetic after the administration of 100 - 200 mg, our results extend previous observation on a linear decrease/increases in plasma Cmax proportional to the dose administered. As previously reported, topiramate half-life was relatively long (see Table 2) and for this reason the wash out period for the present study was set at 21 days, a period long enough to allow the clearance of the drug after each dosing. Finally, it is important to mention that topiramate absorption should not change after food intake, thus the data obtained in the fasting condition reasonably apply to the fed condition.

Topiramate efficacy in epilepsy and migraine is included in several treatment guidelines [5,15-17] and excellent clinical results have been obtained for other pathological conditions such as alcoholism [5]. The overall risk/benefit ratio of its standard use is considered favorable and a recent report dealing with migraine prevention, states that topiramate inclusion in the drug armamentarium used in these patients is one of the outstanding advances of the last ten years in this field [10].


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