Traditional neurology has been dominated by a focus on diagnosis with accurate neuroanatomical localization of the lesion or pathophysiological definition of the underlying disease process. With some notable exceptions, such as changes in the pattern of infectious diseases in the Western world, neurological diseases have not altered much since Gowers (1888) set out the problem. The process of diagnosis, certainly for structurally based conditions, has been immeasurably served by brain imaging, first with X-ray computerized tomography and most recently with magnetic resonance imaging. Pathological study remains a cornerstone of accurate disease classification for some brain disorders, notably tumours, while the pathophysiological basis of many diseases has been elucidated by techniques including molecular biology, clinical neurophysiology and functional brain imaging. However, therapeutics in neurology can be barren, indeed neurology has often suffered the tag of being expert on diagnosis and wanting in treatment. While there can be no doubt that patients seek a label, or explanation, for their problems, treatments, indeed cures, for neurological maladies must be our aim.
Several areas of neurology have seen substantial advances in their therapeutic armamentarium in recent times and it seems appropriate to consider some of the underlying principles that drive neurological therapy and how new therapies may fit such a framework. First, some principles will be covered, after which some specific generic issues will be considered, clinical trial evaluation, dose selection, drug metabolism and interactions, and some issues of special populations.
While everything in neurology, indeed medicine, can be individualized there are some underlying themes. The emphasis on these themes will vary with the condition being considered, and the needs of the patient. However, some part of these principles can be applied in many clinical conditions.
• Patients need an explanation of the condition from which they suffer and how their symptoms fit that diagnosis.
• Patients need to know the natural history of their condition so they can judge the likely benefit of treatments.
• Patients need to know the treatment options, both complementary if they exist, and orthodox.
• It should be made clear whether a treatment will address symptoms or the underlying disease process.
• Realistic goals need to be set for treatment: if the best that can be expected is a 50% improvement this needs to be stated clearly.
• Commonly expected or potentially serious side effects need to be stated and explained.