Manufacturers of drugs and medical devices owe a duty to warn physicians, as learned intermediaries, but not patients, of risks posed by their products. This decision holds that when a manufacturer breaches the duty to warn, the patient must prove that the lack of warning caused the patient harm. To prove causation, the patient need not show that the physician would not have prescribed the drug or device if properly warned. Instead, causation may be proved by showing that the physician would have communicated a stronger warning to the patient and that an objectively prudent person in the patient’s position would have refused the drug or device. If the physician would have continued to recommend the treatment notwithstanding the stronger warning, the plaintiff must prove that an objectively prudent person in the patient’s position would have declined treatment despite the physician’s assessment that the benefits of the treatment for the patient would still outweigh any risks disclosed by a stronger warning.