Carbamazepine
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Reactions 426 - 7 Nov 1992 Carbamazepine Loss of seizure control following generic substitution: 2 case reports Two patients with epilepsy, a 15-year-old boy and a 21-year- old woman, experienced loss of seizure control after switching from 5 months-5 years’ therapy with brand-name carbamazepine (Tegretol (Rm)) 1-1.2 g/day to generic carbamazepine. In both patients, the switch to generic carbamazepine was associated with a reduction in serum carbamazepine concentration. Seizure control was not re- established in either patient, despite a return to Tegretol (Rm) therapy in the boy. Author comment: Carbamazepine possesses poor water solubility and a narrow therapeutic range. Therefore, current methods of assessing the bioequivalence of different carbamazepine formulations may be inadequate. ‘These cases demonstrate a relationship between loss of seizure control and decreased serum carbamazepine concentrations secondary to generic substitution, indicative of a potential bioavailability problem.’ Welty TE, et al. Loss of seizure control associated with generic substitution of carbamazepine. Annals of Pharmacotherapy 26: 775-777, Jun 1992 - USA 800157854 1 Reactions 7 Nov 1992 No. 426 0114-9954/10/0426-0001/$14.95 Adis © 2010 Springer International Publishing AG. All rights reserved
Transcript of Carbamazepine
Reactions 426 - 7 Nov 1992
Carbamazepine
Loss of seizure control following genericsubstitution: 2 case reports
Two patients with epilepsy, a 15-year-old boy and a 21-year-old woman, experienced loss of seizure control after switchingfrom 5 months-5 years’ therapy with brand-namecarbamazepine (Tegretol (Rm)) 1-1.2 g/day to genericcarbamazepine. In both patients, the switch to genericcarbamazepine was associated with a reduction in serumcarbamazepine concentration. Seizure control was not re-established in either patient, despite a return to Tegretol (Rm)therapy in the boy.
Author comment: Carbamazepine possesses poor watersolubility and a narrow therapeutic range. Therefore, currentmethods of assessing the bioequivalence of differentcarbamazepine formulations may be inadequate. ‘These casesdemonstrate a relationship between loss of seizure control anddecreased serum carbamazepine concentrations secondary togeneric substitution, indicative of a potential bioavailabilityproblem.’Welty TE, et al. Loss of seizure control associated with generic substitution ofcarbamazepine. Annals of Pharmacotherapy 26: 775-777, Jun 1992 -USA 800157854
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Reactions 7 Nov 1992 No. 4260114-9954/10/0426-0001/$14.95 Adis © 2010 Springer International Publishing AG. All rights reserved
