<qa>  What is the trial of patients with clinically definite Multiple Sclerosis?This is a comparative drug trial involving patients with clinically definite Multiple Sclerosis and documented neuropathic pain. Patients will be randomized to receive treatment with either paroxetine or pregabalin. After dose titration, participants will complete various pain scale assessments at several points during the study in order to determine the effectiveness of their assigned pain medication. 