Summary judgment is a manufacturer’s goal in almost every case. Often, it’s an uphill battle. For example, a recent Supreme Court decision has made summary judgment more difficult to obtain in prescription drug cases that allege a failure to adequately warn, by limiting the scope of the federal preemption defense.1 Thus, a Food and Drug Administration (“FDA”) decision that a particular risk need not be identified in the labeling is rarely a basis to preclude Plaintiffs from proceeding with litigation criticizing the FDA-approved labeling. Additionally, courts are reluctant to adjudicate, at the summary judgment stage, that labeling adequately warns of the risks at issue because this is perceived by many courts as a question for the jury.2  Moreover, Plaintiffs’ lawyers can easily find “experts” to criticize labeling and to offer opinions that the labeling, albeit FDA-approved, should have disclosed additional or different risks, or disclosed them in a different manner. These expert opinions, even when weakly supported, are often enough to thwart a defense summary judgment motion in most state court actions.  

But even when the alleged risk is not mentioned in the labeling, prescription drug and medical device manufacturers may still have a defense available in failure to warn cases. As set forth in a seminal California case on this subject, Plenger v. Alza Corporation, 11 Cal.App.4th 349 (1992), a manufacturer has no duty to warn of a risk that is well-known and wellappreciated by the medical community. Id. at 362. The manufacturer’s duty to warn runs to the physician under the learned intermediary doctrine3 and there is no duty to warn where the intended audience for the warning is already aware of the risk or should have known of the risk. In addition, if the Plaintiff’s physician is already aware of the risk (or is professionally obligated to be aware of it as common knowledge in the profession), a manufacturer’s failure to warn of such a risk cannot be the proximate cause of any alleged injuries. Id.4 If the physician actually knew of the risk, then the absence of warning on the label would not have prevented the physician’s use of the product. If the physician should have known of the risk but did not, then the proximate cause of the Plaintiffs’ injury was the physician’s failure to know about the risk, not the absence of a warning. In other words, no harm can be caused by failure to warn of a risk already known.5

Courts outside of California have also recognized these defenses.6 For example, as explained in Stanback v. Parke, Davis and Co., 657 F.2d 642 (4th Cir. 1981), there is no evidence of causation when it is firmly established that a more complete warning would not have changed the physician’s course of action in prescribing or administering a prescription drug. Id. at 645-46. In Stanback, Plaintiff brought suit against a pharmaceutical manufacturer for its alleged failure to warn of the risk of Guillain-Barre Syndrome allegedly associated with its influenza vaccine. The lower court granted the manufacturer’s motion for summary judgment holding that its alleged failure to warn was not the cause in fact of Plaintiff’s illness, given the administering physician’s testimony that he independently knew of the risk but chose to administer the vaccine anyway, without communicating the risk to the Plaintiff. Id. at 644. The appellate court affirmed, reasoning that the physician’s testimony conclusively demonstrated that his decisions and actions would not have been affected in the least by the communication of a different warning, therefore breaking the chain of causation that Plaintiff needed to prove in order to survive summary judgment. Id. at 646.

The no duty to warn and the lack of proximate cause defenses are available in several contexts. First, in cases involving older products and established classes of medication, where the risk profile of the medications is well-known, both prescribers and experts are likely to concede this point, especially when confronted at deposition with ample medical literature reporting the risk.7 Likewise, manufacturers may have success with this defense in cases involving off-label pediatric use of a product with a well-appreciated risk profile in adult patients. This defense may also be useful in cases where the alleged undisclosed risk had been the subject of regulatory action or media attention, yet the risk had not yet been inserted in the labeling or did not appear as a Warning/Precaution at the time of use.8

Similarly, the no duty to warn defense is also appropriate in cases where the risk is ever-present (for example, infection followed by death as a result of a surgical procedure) as was the case in Plenger. In Plenger, Plaintiffs filed an action for wrongful death, alleging that the decedent died as a result of an infection caused by her use of an Intrauterine Device (“IUD”) that was manufactured by Defendant. The trial court ruled that the IUD was a prescription device and that the warnings Defendant had given to the decedent’s physician were adequate to preclude liability. The trial court granted summary judgment and entered judgment in Defendant’s favor. The Court of Appeal affirmed, holding that although Defendant did not specifically advise of the risk of death that can result from a pelvic infection, the court held that there was no triable issue of fact on the adequacy of Defendant’s warning, since a manufacturer need not warn of a risk which is readily known and apparent to the consumer—in the case of prescription drugs, the prescriber. The Court explained:

We are aware of no authority which requires a manufacturer to warn of a risk which is readily known and apparent to the consumer, in this case the physician. Further, if the risk of death from untreated infection is universally known in the medical profession, the failure to warn the physician of that risk cannot be the legal cause of the decedent’s death.

Plenger, 11 Cal. App. 4th at 362 (citing Kirsch v. Picker Int’l, Inc., 753 F.2d 670, 671- 672 (8th Cir. 1985)).

Manufacturers should not shy away from this defense in off-label cases. In Huntman v. Danek Medical, Inc., No. 97-2155-IEG RBB, 1998 WL 663362 (S.D. Cal. July 24, 1998), the Defendant obtained summary judgment in a case involving an alleged off-label use of bone screws. Plaintiff alleged the manufacturer improperly marketed and promoted its bone screws for pedicle fixation even though FDA had only approved the use of these screws for anterior fixation. Plaintiff alleged that “but for” the manufacturer’s illegal marketing, she would not have had the screws implanted. In support of its motion for summary judgment, the Defendant manufacturer provided the following evidence regarding the prior knowledge of Plaintiff’s surgeon, Dr. Thompson:  

[P]rior to plaintiff’s surgery, Dr. Thompson had been a physician for over 30 years and had performed between 50–70 spinal fusions with pedicle screws. Dr. Thompson testified that he was aware of the risks involved in these procedures based on his independent research which involved

  1. speaking with other physicians who were performing the procedure;
  2. reading physician-authored articles concerning the procedure; and,
  3. attending symposiums and conferences at which the pedicle screw techniques were presented. Dr. Thompson further testified that (a) he was generally aware of the lack of FDA approval for pedicle fixation from other doctors and (b) defendant’s representative specifically informed him there was no FDA approval for pedicle fixation.

Id. at *5 (citations omitted).  

The District Court found that the uncontroverted testimony of Dr. Thompson demonstrated he had independent knowledge of the risks of pedicle fixation. Thus, the Court granted Defendant’s motion for summary judgment holding that the adequacy of the warnings is immaterial where the doctor knows of the specific risks.


In summary, armed with medical literature and case reports in a failure to warn case involving a prescription medication or medical device with a long history of use, welldefined risks, or recent publicity and/or regulatory action, Defense counsel may well be able to elicit deposition testimony from the prescriber which not only concedes that the relevant risk is well-known in the medical community but also that he or she was specifically aware of the risk. In those situations, the chance of obtaining summary judgment based on lack of duty or proximate cause is increased. Likewise, if the prescriber is not available for deposition or if a summary judgment motion can be filed without prescriber testimony, a manufacturer may use expert testimony, medical literature, and medical texts to demonstrate to a court’s satisfaction that a risk was well-known in the medical community, thus negating any legal obligation for the manufacturer to warn of the risk at issue.