Are some doctors too old to practice medicine?

In September 2011, a patient went to Dr. Seymour Leven, 88, at the Lewis County Mental Health Center in Lowville, New York asking for a prescription of Oxycontin. The painkiller is prone to abuse, and Leven knew the patient had tendencies in that direction, but eventually filled the prescription on an emergency basis, on the condition that he immediately admit himself to the nearest detox facility. The patient walked out — prescription in hand—and instead of seeking the help he needed, shopped around, filling prescriptions for the same drug after conning other area doctors. The federal Drug Enforcement Administration picked up on it, fingered Leven for improper prescribing and urged the state's Office of Professional Medical Conduct to take action.