This article discusses how coexisting medical illnesses interact with aging to complicate the body's ability to safely process drugs. The article also discusses prescription drug misuse, abuse, and dependency by the elderly.
Finlayson, Richard E.
"Prescription Drug Use by the Elderly,"
Marquette Elder's Advisor:
2, Article 12.
Available at: http://scholarship.law.marquette.edu/elders/vol2/iss2/12