The present invention is directed to methods of reducing symptoms associated with an abrupt reduction in an endogenous or exogenous chemical in subjects, the methods comprising: (a) administering to the subject a single dosage form comprising an active agent, wherein the release rate of the active agent from the single dosage form tapers throughout the administration； and (b) removing the single dosage form from the subjects after the release rate of the active agent is at or below a terminal symptom threshold level.
