The Learned Intermediary Doctrine provides that a drug or medical device manufacturer has no legal duty to warn consumers of a drug or medical device’s harmful side effects if that information has been communicated to a “learned intermediary.”
The best example of a learned intermediary is a patient’s personal physician. The physician’s specialized medical training enables him or her to interpret the warnings provided by the manufacturer. As the intermediary between the manufacturer and the patient, the physician is best situated to decide whether the warnings apply to the patient, given the patient’s symptoms and condition. Should the drug or medical device cause the patient subsequent injury, as the learned intermediary, the prescribing physician could face legal liability for failing to warn the patient of harmful side effects (provided that the physician was adequately warned by the manufacturer).
Generally, manufacturers provide warnings to learned intermediaries via the inserts in the packaging of a drug or medical device. In developing these warnings, manufacturers must consider any regulatory guidelines from the Food and Drug Administration or similar agency. Further, from a practical standpoint, the warning should:
A manufacturer’s duty to warn extends only to those harmful effects that the manufacturer is aware of or has reason to know. Manufacturers have a continuing obligation to ensure warnings are updated based on new information or research.
Although manufacturers should make every effort to keep their warnings up-to-date, failure to do so does not necessarily eliminate the protections afforded by the Doctrine. For example, if the learned intermediary became aware of a drug or medical device’s harmful side effects from sources other than the manufacturer, the Doctrine may still apply.
Perhaps the most notable exception to the Doctrine concerns mass immunizations, such as flu vaccines, etc. While the manufacturer communicates the required warnings to the learned intermediary, the learned intermediary may not be present when the patient is inoculated. This means that the learned intermediary cannot assess the patient’s physical conditions, discuss any symptoms, or provide any warning information. In these instances, the manufacturer must ensure that the warnings are provided to the patient directly or require the entity giving the inoculation to provide the information to the patient at the time of inoculation.