(NewsNation) — The Food and Drug Administration launched a crackdown on misleading pharmaceutical advertising Tuesday, sending thousands of warning letters and approximately 100 cease-and-desist letters to drug companies.

The FDA will also initiate rulemaking to eliminate the so-called "adequate provision" loophole created in 1997, which allowed drug companies to provide only brief safety warnings in broadcast and digital advertisements while directing consumers to websites or phone numbers for complete risk information.

The enforcement action was announced alongside President Donald Trump's signing of a presidential memorandum directing federal regulators to increase transparency requirements for prescription drug advertisements.

Trump signs action to strengthen prescription drug ad re

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