Controlled release formulations having rapid onset and rapid decline of effective plasma drug concentrations

An oral controlled release formulation which provides a rapid onset of therapeutic effect and a rapid drop in plasma concentration after a prolonged period of therapeutic effect, comprising

• a plurality of substrates comprising a portion of an effective dose of methylphenidate hydrochloride in immediate release form,
• a hydrophobic material comprising an acrylic polymer, coated onto the surface of said substrates in an amount sufficient to retard the release of said drug,
• an enteric coating applied over said hydrophobic coating in an amount sufficient to substantially delay the release of said drug from said substrate until after said formulation passes through the stomach, wherein said enteric coating is derived from an aqueous dispersion comprising an acrylic/methacrylic copolymer, a plasticizer and a glidant,
• the formulation further comprising the remaining portion of said methylphenidate hydrochloride in immediate release form, and
• wherein the formulation provides a time to maximum plasma concentration of said methylphenidate hydrochloride at about 0.5 to about 4 hours after oral administration.