Provided are methods of delivering at least one pharmaceutical agent to the central nervous system (CNS) of a subject, methods of treating a neurological disorder or pain in a subject that include administering at least one pharmaceutical agent onto a SEM graft in the skull base of the subject. Also provided are methods of treating a neurological disorder or pain in a subject that include forming a SEM graft in the skull base of the subject and administering at least one pharmaceutical agent onto the SEM graft in the skull base of the subject. Also provided are methods of forming a SEM graft in the skull base of a subject, compositions for administration onto a SEM graft in the skull base or into an endonasal reservoir or endonasal reservoir device in a subject, and devices for administering such compositions onto a SEM graft in the skull base of a subject.