A study to determine lipid changing effects of MK0524A when compared to niacin extended release (NIASPAN) and placebo.

Inclusion Criteria:

• Patients must be between the ages of 18 and 70 years
• Female patients must be pre-menopausal women that have been surgically sterilized, not pregnant and/or not planning to become pregnant

Exclusion Criteria:

• Patient has a history of peptic ulcer or gout
• Patient is sensitive to niacin or products containing niacin
• Patient drinks more than 2 alcoholic drinks per day
• Patient has certain heart disease, cancer, or is HIV positive