A buccal and/or sublingual formulation comprising one or more active compounds and a buccal matrix which releases the active compounds at a predetermined rate for transport across the buccal and/or sublingual membranes, wherein the rate of release of the active compounds is either (A) the same or substantially the same rate at which the active compounds are transported across the buccal and/or sublingual membranes or (B) a rate which releases the active compounds over an extended period as required by the therapeutic affect or treatment window for those active compounds.