When Did Part D Medicare Go Into Effect? 
Part D Medicare went into effect on Jan 1 , 2006 . The Voluntary Prescription Drug Program was added to the Social Security Act by a ruling called The Medicare Prescription Drug , Improvement , andModernization Act -LRB- MMA -RRB- of 2003 . It allows persons enrolled in Part A and B Medicare to enroll in Part D for prescription drug benefits . 