In McKee v. American Home Products Corp., 113 Wn.2d 701, 782 P.2d 1045 (Wash. 1989), the plaintiff received prescriptions from her doctor for an appetite suppressant known as Plegine. See McKee, 782 P.2d at 1046. The Physician's Desk Reference entry for Plegine cautions that it is a potentially addictive amphetamine; therefore, its use should be discontinued within a few weeks to avoid addiction. See id. Notwithstanding, McKee's doctor authorized refills of the drug for ten years, and two pharmacists filled the prescriptions without warning McKee of the possible side effects of extended use. See McKee, 782 P.2d at 1047. McKee sued the drug manufacturer, the prescribing physician, and the pharmacists for damages sustained as a result of her addiction to Plegine. See id. McKee argued that her pharmacists were negligent in selling her Plegine without warning of its adverse effects and for failing to provide her the drug manufacturer's package insert. See id. In a 5-4 decision, the Washington Supreme Court concluded that the learned intermediary doctrine, normally applied to the relationship among physician, patient, and manufacturer, applied with equal force to the relationship among physician, patient, and pharmacist. See McKee, 782 P.2d at 1050-51. The court reasoned that in both circumstances, the physician was in the best position to "relate the propensities of the drug to the physical idiosyncrasies of the patient." McKee, 782 P.2d at 1050. The court therefore held that McKee's pharmacists did not have a duty to warn her of the dangerous propensities of Plegine, nor were they legally obligated to give her the drug manufacturer's package insert containing such warnings. See McKee, 782 P.2d at 1054-55.