Spending on prescription drugs nationwide has been slowing for years, reports the New York Times, because of the increasingly widespread use of low-cost generics. But in 2012, something unheard-of happened: money spent on prescription drugs actually dropped. But some are warning that the ever-expanding use of generics has masked a growing problem for the government, insurers and others who pay the bill for prescription drugs: the rising cost of complex specialty medicines that treat cancer, rheumatoid arthritis and other diseases.