Inclusion Criteria:

• You are between the ages of 45-75
• You are a man or non-pregnant woman
• You agree to not eat or drink fruit or fruit juices (orange, apple or grapefruit) for 2 weeks before starting study medication

Exclusion Criteria:

• You have smoked or used other nicotine-containing products (chewing tobacco) within the last 6 months
• You have used St. John's Wort or any products that include it within the last 2 weeks
• You have used herbal, organic, dietary or nutritional remedies within the last 2 weeks
• You have a history of drug allergies (anaphylaxis, angioedema)
• You have taken an investigational drug in another clinical trial within the last 4 weeks
• You have a history of cardiovascular disease including hypertension (high blood pressure)
• You have a history of renal disease
• You have a history of gall bladder disease or have had abnormal liver function tests
• You have a history of drug or alcohol abuse
• You drink more than 6 cups of caffeinated beverages a day (coffee, tea or cola)