Drugs Used in Neurodegenerative Disorders

Neurodegenerative diseases are a group of disorders characterized by neuronal loss and generally an accumulation of insoluble intracellular or extracellular material in certain brain regions. Most neurodegenerative disorders are of unknown etiology, affect the elderly, are progressive, and damage selected neuronal populations or brain regions. There are some inherited forms of these disorders; however, most are sporadic occurrences (idiopathic) with genetic predisposition, environmental factors, and aging contributing as risk factors. The neurodegenerative disorders include (1) Alzheimer’s disease, the most common cause of dementia, in which the neural injury is primarily in the hippocampus and cortex; (2) Parkinson’s disease, a disabling motor impairment disorder due to the loss of nigrostriatal dopamine neurons; (3) Huntington’s disease, a motor disease characterized by excessive and abnormal movements resulting from the loss of a specific subset of striatal neurons; (4) amyotrophic lateral sclerosis (ALS), in which progressive weakness and muscle atrophy are due to degeneration of spinal, bulbar, and cortical neurons. This chapter focuses on Parkinson’s and Alzheimer’s diseases, for which pharmacological intervention can alleviate the clinical symptoms. However, drugs used in the treatment of neurodegenerative disorders only treat symptoms and do not cure or alter the progression of the disease.