Faster drug approvals in the US and Canada are not linked to increases in the number of serious drug safety warnings issued by regulators, nor to actual evidence of health risks, according to new research. Investigators compared data about the number of drug safety warnings issued by regulators in the US and Canada to the number of actual discontinuations of new drugs due to safety concerns over a 20-year period. They found that, despite the increased issuance of safety warnings by regulators in both countries over the period from 2002 to 2011, the rate of discontinuation of new drugs from the market was somewhat smaller than in the period from 1992 to 2001. The authors concluded that changes in the regulatory behavior of drug approval agencies offers a better explanation for the increased issuance of serious warnings than does an alleged increase in the approval of more dangerous drugs. The article is available for free download from Canadian Health Policy, the online journal of the Canadian Health Policy Institute (CHPI).