title: Conversion from thrice daily to twice daily administration of gabapentin (GBP) in partial epilepsy: analysis of clinical efficacy and plasma levels.
abstract: Gabapentin has been administered in placebo-controlled studies with a thrice daily (T.I.D.) schedule, because of its short half-life. However, clinical efficacy does not seem strictly related to plasma levels: a twice daily (B.I.D.) schedule might therefore be possible. The aim of our study was to verify if the conversion from a T.I.D. to a B.I.D. regimen affected the efficacy and safety of gabapentin therapy. Out of 171 patients treated with add-on gabapentin, we selected 29 stable responders, who were followed for three months with a T.I.D. schedule and then switched to B.I.D. regimen for further three months. Seizure number, side-effects and trough plasma levels of gabapentin were collected during both periods. Gabapentin mean dose was 2117.2 mg/day. Mean number of seizures/months was: 4.2 at baseline, 1.0 during the T.I.D., and 0.9 during the B.I.D. period. Mean trough plasma level of gabapentin was 5.9 microgram/ml during the T.I.D. and 5.2 microgram/ml during the B.I.D. period. Twelve side-effects were reported by 11 patients during the T.I.D. and 6 by 5 patients during the B.I.D. period., sedation and vertigo were the most frequent in both. Results of our study suggest that gabapentin can be administered safely and effectively either with a T.I.D. and a B.I.D. regimen.
authors.affiliation: Epilepsy Center, Department of Neurology, Careggi Hospital, Florence, Italy.
authors.forename: G C
authors.initials: GC
authors.lastname: Muscas
authors.forename: S
authors.initials: S
authors.lastname: Chiroli
authors.forename: F
authors.initials: F
authors.lastname: Luceri
authors.forename: M D
authors.initials: MD
authors.lastname: Mastio
authors.forename: F
authors.initials: F
authors.lastname: Balestrieri
authors.forename: G
authors.initials: G
authors.lastname: Arnetoli
mesh_terms: D000085:Acetates / Q000008:administration & dosage* / Q000097:blood* / Q000493:pharmacokinetics; D000293:Adolescent; D000328:Adult; D000588:Amines; D000927:Anticonvulsants / Q000008:administration & dosage* / Q000097:blood* / Q000493:pharmacokinetics; D018592:Cross-Over Studies; D003509:Cyclohexanecarboxylic Acids; D004334:Drug Administration Schedule; D004828:Epilepsies, Partial / Q000188:drug therapy*; D005260:Female; D000077206:Gabapentin; D006801:Humans; D008297:Male; D008875:Middle Aged; D019338:Polypharmacy; D016896:Treatment Outcome; D005680:gamma-Aminobutyric Acid
chemical_list: D000085:Acetates; D000588:Amines; D000927:Anticonvulsants; D003509:Cyclohexanecarboxylic Acids; D005680:gamma-Aminobutyric Acid; D000077206:Gabapentin