Summary: Results are described on the association of increased serum glutamic oxaloacetic transaminase (SGOT) and serum glutamic pyruvic transaminase (SGPT) activities with valproic acid (VPA) and coantiepileptic drug therapy in a group (n = 126) of randomly selected chronically medicated outpatients. The highest incidence (SGOT, 28.3%; SGPT, 26.1%) of elevations occurred in patients comedicated with VPA-phenobarbital (PB)-phenytoin (PHT) combinations, followed by those in the VPA-PB group (SGOT, 19.5%; SGPT, 7.3%). No SGPT elevations were detected in any patients (n = 40) on chronic VPA monotherapy, while SGOT was marginally elevated in 20% of the cases. Considering the total sample (n = 126), SGOT activities were found to be linearly and directly correlated with VPA plasma concentration (n = 126, r = 0.228, p > 0.01), PB concentration (n = 86, r = 0.352, p > 0.01), PHT concentration (n = 45, r = 0.336, p > 0.01), sum of VPA-PB concentrations (n = 86, r = 0.440, p > 0.001), and sum of VPA-PB-PHT concentrations (n = 45, r = 0.481, p > 0.001). The corresponding correlations for SGPT activities were similar, except that no correlation was observed in the case of VPA monotherapy. Student's t tests for equality of means showed that the subgroup with abnormal enzyme activities had a significantly higher mean plasma concentration for PB, PHT, sum of VPA-PB, and sum of VPA-PB-PHT when compared with normal enzyme subgroup patients. Furthermore, linear regression analyses of the abnormal enzyme activities and antiepileptic drug concentration produced direct significant correlation in the case of SGOT with sum of VPA-PB concentrations (n = 20, r = 0.587, p > 0.01), and with sum of VPA-PB-PHT concentrations (n = 12, r = 0.592, p > 0.025). Patients on VPA and coantiepileptic drug therapy (PB and PHT) are the most likely group to show abnormal SGOT and SGPT activities. None of the patients had SGOT activities higher than twice the upper limit of normal or SGPT activities higher than thrice. Such mild elevations do not appear to be clinically significant and are probably due to enzyme induction.
Results are described on the association of elevated ammonia (NH3) with valproic acid (VPA) therapy in a large group (n = 157) of randomly selected, chronically medicated (greater than 2 years) outpatients. The highest incidence (45.5%) of elevations occurred in patients comedicated with VPA-phenobarbital (PB)-phenytoin (PHT) combinations, followed by VPA-PB (33.3%) and VPA-PHT (15.4%). No NH3 elevations were detected in all patients (n = 38) on chronic VPA monotherapy. Considering the total sample (n = 157), NH3 concentrations were found to be linearly and directly correlated with VPA plasma concentration (n = 125, r = 0.249, p less than 0.001), PB concentration (n = 86, r = 0.411, p less than 0.001), sum of VPA-PB concentration (n = 60, r = 0.721, p less than 0.001), and sum of VPA-PB-PHT concentration (n = 33, r = 0.802, p less than 0.001). When patients in the subgroups (n = 73) that included all the patients with elevated NH3 were separated into one group (n = 47) with normal NH3 (less than or equal to 0.70 micrograms/ml) and one group (n = 26) with elevated NH3 (greater than or equal to 0.71 micrograms/ml), Student's t tests for equality of means showed that the group with elevated NH3 had a significantly higher mean plasma concentration for VPA, PB, sum of VPA-PB, and sum of VPA-PB-PHT (all at p less than 0.001) when compared with the normal group.(ABSTRACT TRUNCATED AT 250 WORDS)