Abstracts

Lamotrigine (LTG) is a commonly prescribed antiepileptic drug. We are studying LTG pharmacokinetics (PK) in young and elderly patients with an intravenous, stable-labeled LTG formulation. This is a preliminary report on the safety and tolerability of the formulation., Adult patients ([gt] 18 years) without significant cardiac problems or interacting co-medications were enrolled. Patients on steady-state maintenance LTG therapy were given a single 50 mg replacement dose of the [13C2,15N]-LTG (SL-LTG) formulation as part of their daily regimen. The remainder of their daily dose was given orally. Blood pressure (BP) and heart rate (HR) data were collected prior to infusion, every 2 minutes during infusion, and every 15 minutes for the first hour following the completion of the infusion. An EKG was taken before and during the infusion. The mean and standard deviation of HR and BP at baseline, end of infusion, and 30 minutes post-infusion were determined. A value of p [le] 0.05 was considered significant. The study nurse monitored the infusion site for inflammation during the infusion and at the time that the indwelling catheter was removed. Patients were asked during the infusion if they were experiencing discomfort at the infusion site or any other symptoms., Five younger women (age 25-48 years) have completed the study. LTG daily doses ranged from 200-800 mg/day. There were no significant changes from baseline in EKG in any of the subjects studied. Table 1 presents the changes in vital signs in subjects as compared to their baseline, pre-infusion time point. The minimum and maximum observed BP or HR did not occur at the same time in each individual. No subject reported discomfort at the injection site or any adverse events. There was no evidence of inflammation at the site of infusion., Our preliminary data indicate that this intravenous LTG formulation is safe and well tolerated when administered to relatively healthy adult patients.[table1], (Supported by NINDS P-50NS16308 and MO1-RR00400, M01-RR00039.)