Comparative pharmacokinetic analysis of a novel sustained release dosage form of valproic acid in dogs

A new sustained release dosage form of valproic acid (VPA) was developed. The new sustained release dosage form was administered (twice, with and without food) to five dogs in comparison to a standard tablet (Depakine, Labaz) and an i.v. preparation of the drug. Drug level monitoring in the plasma was performed by a GLC assay. Results indicate that the sustained release formulation exhibited a more prolonged and uniform absorption rate, yielded more sustained plasma levels after ingestion, and showed an overall bioavailability of 0·84 (95 per cent C.I. = 0·72, 0·96) relative to an equivalent dose of a conventional tablet.