Patient description: A 57-year old farmer was diagnosed with Parkinson's disease a year ago. He experiences slowness of movement and tremors. His past medical history is significant for hypertension and hypercholesterolemia. He lives with his wife. They have three children. He used to be active with planting and taking care of their farm animals before his diagnosis. The patient complains of shaking and slow movement. He had difficulty entering through a door, as he was frozen and needed guidance to step in. His handwriting is getting smaller. He is on Levodopa and Trihexyphenidyl. He stated his medications help with shaking and slow movement. But he still has difficulty initiating movements, stiffness and slowness in general. He is an alert and cooperative man who doesn't have any signs of dementia. He doesn't smoke or use any illicit drugs.

Clinical trial eligibility criteria: eligible ages (years): 18.0-999.0,  Healthy Is the individual a healthy, normal adult man and woman who volunteers to participate? ls s/he at least 18 years of age? Is his/her BMI between 19 and 30, inclusive? Is she willing .to avoid pregnancy by abstaining from sexual intercourse with a non-sterile male partner, or by the use one of the following methods: diaphragm + spermicide or condom + spermicide (at least 14 days before dosing), intra uterine contraceptive device or hormonal contraceptives (at least 4 weeks prior to dosing), or has she been surgically sterile or post-menopausal at least six months prior to entering into the stndy? Is s/he considered .reliable and capable of understanding his/her responsibility and role in the study Has s/he provided written informed consent? A no answer to any of the above questions indicated that the individual was ineligible for enrollment  Does the individual have a history of allergy or hypersensitivity to amlodipine? Does s/he have clinically significant laboratory abnormalities that would interfere with the conduct or interpretation of the study or jeopardize his/her safety? Does s/he have significant history or clinical evidence of auto-immune, cardiovascular, gastrointestinal, hematological, hematopoietic, hepatic, neurological, ongoing infection, pancreatic, or renal diseases that would interfere with the conduct or interpretation of the study or jeopardize his/her safety'? Is she nursing? Does s/he have serious psychological illness? Does s/he have significant h/story (within the past year) or clinical evidence of alcohol or drug abuse? • Does s/he have a positive urine drug screen or a positive HIV-1, or hepatitis B or C screen, or a positive pregnancy test? Has s/he consumed grapefruit or grapefruit juice during the 7rday period preceding study initiation? Is s/he unable to refrain from the use of alcohol or xanthine-containing foods or beverages during periods beginning 48 hours prior to study drug administration and ending when the last blood sample has been taken in each study period? Has s/he used any prescription drug, other than hormonal contraceptives, during the 14-day period prior to study initiation, or any OTC drug during the 72-hour period preceding study initiation? Is s/he unable to refrain from the use of all concomitant medications, other than hormonal contraceptives, during the study? Has s/he donated or lost blood, or participated in a clinical study which involved the withdrawal of a large volume of blood (480 mL or more), during the six week period preceding study initiation? Has s/he donated plasma during the two week period preceding study initiation? Has s/he received an investigational drug during the 30 day period preceding study initiation? Is s/he a heavy smoker (usually smoking more than 10 cigarettes per day)?