The effects of mildronate [3-(2,2,2-trimethylhydrazinium) propionate], an inhibitor of L-carnitine biosynthesis and an anti-ischaemic drug, were examined in various in-vivo conditions to investigate the neuropharmacological profile after acute administration. Mildronate (200 mg/kg, acute intraperitoneal administration) exerted anticonvulsant activity in a chemoconvulsant pentylenetetrazole-induced clonic and tonic seizure test but did not change the effects of a convulsion-inducing dose of (+)-bicuculline, a gamma-aminobutyric acid receptor antagonist. Mildronate also dose-dependently inhibited the sleeping time in ethanol-induced loss of righting reflex test. However, in a pentylenetetrazole-induced seizure test, mildronate significantly stimulated the anticonvulsant activity of ethanol. The anticonvulsant activity of mildronate was completely blocked after pre-treatment with alpha2-adrenergic receptor antagonist yohimbine (2 mg/kg) and nitric oxide synthase inhibitor N(G)-nitro-L-arginine (10 mg/kg). These results show that the acute administration of mildronate induces anticonvulsant and antihypnotic effects, which involve alpha2-adrenergic receptor and nitric oxide -dependent mechanisms. These findings indicate that the acute administration of mildronate could be beneficial for the treatment of seizures and alcohol intoxication.