The present invention concerns compositions, methods and/or apparatus of central administration of various CNS-active agents. In particular embodiments, intrathecal administration is advantageous for decreasing the systemic concentrations of CNS agent, thereby decreasing side effect toxicity, while allowing more effective delivery of the agent to the site of action, simultaneously decreasing the dosage delivered to the subject. In particular embodiments, ICV delivery may be of use for patients who have previously proven to be refractory to systemic administration of CNS agents, in some cases due to systemic side effects, or for those patients whose symptoms are of sufficient severity to warrant more aggressive therapeutic intervention. ICV administration allows not only lower systemic concentration but also higher therapeutically effective concentration within the CNS.