After it begins to sell a drug, a manufacturer has continuing obligations with respect to the drug’s safety.49 These include an obligation to add an additional warning to the label “as soon as there is reasonable evidence of a causal association” between a drug and a clinically significant hazard.50 Indeed, pursuant to a regulatory measure known as the “Changes Being Effected” provision, a manufacturer can immediately revise a drug’s label, without first obtaining FDA approval, if the change gives doctors reason to be more cautious about the drug.51 This includes deleting from the label any “false, misleading, or unsupported indications” about the drug’s use or effectiveness, as well as adding or strengthening statements on the label about “a contraindication, warning, precaution, or adverse reaction” or “an instruction about dosage and administration that is intended to increase the safe use of the drug product.”52