A solvent used for antiepileptic drugs increases serum and brain zonisamide concentrations in seizure-susceptible el mice.
Effects of a solvent mixture commonly used to dissolve antiepileptic drugs on the anticonvulsive effect as well as serum and brain concentrations of zonisamide (ZNS), a sulfonamide derivative, were investigated. The solvent mixture consisted of propylene glycol (PG, 40%) and ethanol (10.5%) in saline (PES). Intraperitoneal administration of ZNS at 25, 50, and 75 mg/kg dissolved in PES suppressed seizures in the EL strain of mice more effectively than the same doses of ZNS in saline. Serum and brain concentrations of the drug were significantly higher with PES than with saline as the vehicle for administration. At a dose of 75 mg/kg ip, both serum and brain ZNS concentrations in mice treated with ZNS in PES remained significantly higher than concentrations in mice treated with ZNS in saline from 1 to 6 hours after injection. PES mixtures including PG may not be suitable solvents for antiepileptic drugs in experiments investigating anticonvulsive effects.
Nagatomo
I
I
Department of Neuropsychiatry, Faculty of Medicine, Kagoshima University, 8-35-1, Kagoshima, 890-8520, Japan.
Akasaki
Y
Y
Hashiguchi
W
W
Tominaga
M
M
Uchida
M
M
Takigawa
M
M