Drug Shortages Shelf Life Extension Act This bill requires the Food and Drug Administration (FDA) to issue or revise guidance to address issues relating to extending drug expiration dates. Specifically, the guidance must address recommendations to drug companies relating to (1) submitting stability testing data in applications for market approval for drugs or biological products; and (2) establishing on drug labels the longest feasible expiration date supported by such data, taking into consideration how extended expiration dates may help prevent or mitigate drug shortages. The FDA must also periodically report to Congress certain information about requests to change the expiration date on a drug label, including the number of such requests from the FDA to the manufacturer and the rationale for each request.