F I L E D
United States Court of Appeals
Tenth Circuit
PUBLISH
JUL 17 2001
UNITED STATES COURT OF APPEALS
PATRICK FISHER
Clerk
TENTH CIRCUIT
MARK W. ECK, SANDRA K. ECK,
TRAVIS ECK and MEGAN ECK,
Plaintiffs-Appellants,
v. No. 00-7020
PARKE, DAVIS & COMPANY,
WARNER-LAMBERT COMPANY,
THE RUGBY GROUP, INC., AND
RUGBY LABORATORIES, INC.,
Defendants-Appellees.
Appeal from the United States District Court
for the E.D. Oklahoma
(D.C. NO. 99-CV-156-S)
Steven E. Aldous, Slack & Davis, L.L.P., Austin, Texas, for Appellants.
Brad Smith (Mike Barkley with him on the brief) of Barkley Titus Hillis &
Reynolds, Tulsa, Oklahoma, for Appellees Parke, Davis & Company and Warner-
Lambert Company.
Thomas E. Steichen (Richard M. Eldridge with him on the brief) of Rhodes,
Hieronymus, Jones, Tucker & Gable, P.L.L.C., Tulsa, Oklahoma, for Appellees
The Rugby Group, Inc. and Rugby Laboratories, Inc.
Before HENRY and MURPHY , Circuit Judges, and VAN BEBBER , District
Judge. *
HENRY, Circuit Judge.
Mark W. Eck, suffering from injuries sustained from an onset of liver
failure, brought, together with members of his family, this products liability
action 1 against defendants Parke, Davis & Company and Warner-Lambert
Company (jointly, “Warner-Lambert”) and the Rugby Group, Inc. and Rugby
Laboratories, Inc. (jointly, “Rugby”). 2
The Ecks contended that Mr. Eck’s liver
failure resulted from the interaction of two prescription drugs: (1) Dilantin, an
anti-convulsant, which is manufactured and distributed by Warner-Lambert, and
(2) Isocet (which contains acetaminophen, butalbital and caffeine), and which is
distributed by Rugby. The defendants filed a motion for summary judgment in the
district court, which the district court granted. The district court found that the
*
The Honorable G. Thomas Van Bebber, United States Senior District
Judge for the District of Kansas, sitting by designation.
1
Sandra Eck, the wife of Mark Eck, brought a claim for loss of spousal
consortium. Two of Mark Eck’s children, Travis and Megan Eck, brought claims
for loss of parental consortium.
Plaintiffs also sued Hoechst Marion Roussel, Inc. and Watson
2
Pharmaceuticals, Inc., who were dismissed from this action by the district court.
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Ecks’ claims were barred by the learned intermediary doctrine. For the reasons
set forth below, we affirm the district court’s decision. We are called upon to
decide only the liability of these defendants; the liability of other actors is not
before us.
I. BACKGROUND
The following facts are undisputed. Mr. Eck is a pharmacist who owns and
operates Eck Pharmacy in Healdton, Oklahoma. In 1992 or 1993, Dr. Mark
Newey became Mr. Eck’s treating physician. On March 13, 1994 and on January
19, 1995, Dr. Newey prescribed Isocet to Mr. Eck to treat his complaints of
tension headaches. At the time the Isocet was prescribed by Dr. Newey, Mr. Eck
was not taking Dilantin.
Mr. Eck has a history of mild temporal lobe seizures. In October 1996, Dr.
Newey prescribed Tegretol, another anti-convulsant medication, after Mr. Eck
began to experience seizures. While on the Tegretol, Mr. Eck developed a rash
and Dr. Newey referred him in mid-December 1996 to Dr. Dan Udonta, who, in
turn, prescribed Depakote in lieu of the Tegretol. Mr. Eck again developed a
rash. On January 31, 1997, Dr. Udonta referred Mr. Eck to Dr. Nancy Rodgers,
an epilepsy specialist.
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Five days later Mr. Eck experienced another seizure-related episode. Dr.
Newey came to Mr. Eck’s house and consulted with Dr. Rodgers via telephone.
Mr. Eck was admitted to the Healdton Hospital emergency room on February 5,
1997. Dr. Newey ordered a 900 mg loading dose of Dilantin that was given to
Mr. Eck. He was discharged on February 6, 1997, and sent by Dr. Newey to see
Dr. Rodgers. Thereafter, Dr. Rodgers removed Mr. Eck from the Depakote and
prescribed Dilantin to control his seizures. Dr. Newey monitored his Dilantin
levels during the time Dr. Rodgers prescribed Dilantin.
On April 5, 1997, Mr. Eck began to feel anxious. On April 7, 1997, he
began experiencing a tension headache and took two Isocet tablets (each
containing 325 mg of acetaminophen) from his January 19, 1995 prescription.
During this period of time, Mr. Eck was also taking Dilantin, prescribed in
February by Dr. Rodgers to control his seizures. He had taken 400 mg of Dilantin
that day.
On April 8, 1997, Mr. Eck began vomiting repeatedly and his condition
continued to deteriorate. Dr. Newey admitted him to Mercy Hospital in Ardmore,
Oklahoma. At Mercy Hospital, Mr. Eck was diagnosed with acute liver failure
and he was transported to Baylor Medical Center in Dallas, Texas. A liver biopsy
revealed that Mr. Eck’s liver failure was consistent with acetaminophen
poisoning. As a result of his liver failure and related complications, Mr. Eck was
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in a coma and on a ventilator for 36 days. He underwent various surgeries and
had an extended hospital stay.
In granting the defendants’ motion for summary judgment, the district court
found that Oklahoma’s “learned intermediary doctrine” shielded Warner-Lambert
and Rugby from liability because any failure to warn was not the proximate cause
of Mr. Eck’s injuries. The district court found summary judgment inappropriate
with respect to the two related grounds of (1) no duty to warn when there is no
known danger of the interaction of the drugs at therapeutic levels, and (2) the
absence of medical causation. Because we affirm for the reasons given below, we
need not address the appropriateness of the denial of summary judgment on these
grounds.
On appeal, the Ecks challenge: (1) the district court’s decision to limit its
focus of inquiry to the testimony of Dr. Rodgers, the physician who prescribed
Dilantin, and not to consider the testimony of Dr. Newey, the prescribing
physician for Isocet; (2) the district court’s conclusion that Dr. Rodgers’
testimony rebutted the presumption that had an adequate warning been provided,
it would have been read and heeded; and (3) the district court’s finding that no
issues of material fact regarding causation existed. After we review the
progression and rationale of the learned intermediary doctrine, we shall discuss
each contention in turn.
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II. INITIAL MATTERS
A. Standard of Review
This diversity action is governed by Oklahoma’s substantive tort law, but
we are governed by federal law in determining the propriety of the district court’s
grant of summary judgment. See Pegasus Helicopters, Inc. v. United Techs.
Corp. , 35 F.3d 507, 510 (10th Cir. 1994). “We review the entry of summary
judgment de novo, drawing all reasonable inferences in favor of the nonmovants.
Summary judgment is appropriate only when the moving party shows there is no
genuine issue as to any material fact and that the moving party is entitled to a
judgment as a matter of law. To avoid summary judgment, the nonmovant must
make a showing sufficient to establish an inference of the existence of each
element essential to the case. The nonmovant may not rest upon mere allegation
or denials of his pleadings, but must set forth specific facts showing that there is
a genuine issue for trial.” Hulsey v. Kmart, Inc. , 43 F.3d 555, 557 (10th Cir.
1994) (quotations and citations omitted).
B. Failure to Warn and the Learned Intermediary Doctrine
The Ecks contend that Warner-Lambert and Rugby, by failing to label their
products with adequate warnings of Dilantin’s propensity to interact with
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acetaminophen, placed defective and unreasonably dangerous products in the
market place that caused Mr. Eck’s liver failure. The Ecks also contend the
defendants were negligent in the designing, testing, warning, and marketing of
their products through their failure to provide adequate instructions or warnings
and by misrepresenting the safety of their products when used in conjunction with
one another.
To recover in a failure to warn case, a plaintiff must establish both cause-
in-fact (that the product in question caused the injury) and proximate cause (that
the manufacturer of the product “breached a duty to warn of possible detrimental
reactions”). McKee v. Moore , 648 P.2d 21, 23-24 (Okla. 1982). To qualify as a
proximate cause of the injury, the breach of a duty or failure to warn must be a
substantial contributing factor in bringing about the harm in question. See
Woolard v. JLG Indus. Inc. , 210 F.3d 1158, 1172 (10th Cir. 2000) (applying
Oklahoma law) (noting that “a proximate cause is defined as one that, in the
natural and continuous sequence, produces the plaintiff’s injury and without
which the injury would not have happened”); Van Buskirk v. Carey Canadian
Mines, Ltd. , 760 F.2d 481, 492 (3d Cir. 1985) (applying Pennsylvania law)
(internal quotation marks omitted).
Oklahoma’s products liability law “generally requires a manufacturer to
warn consumers of danger associated with the use of its product to the extent the
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manufacturer knew or should have known of the danger.” Edwards v. Basel
Pharms. , 933 P.2d 298, 300 (Okla. 1997). Certain products, including
prescription drugs, are “unavoidably unsafe products” that cannot be made
completely safe, but serve a public benefit. See id. ; Restatement (Second) Torts §
402A cmt. k (1965) (the “Restatement”). Oklahoma law recognizes that drug
manufacturers cannot be strictly liable merely because of the dangerous
propensities of such products. See Edwards , 933 P.2d at 300. Such products, if
“properly prepared, and accompanied by proper directions and warning[s, are] not
defective, nor [are they] unreasonably dangerous.” Restatement § 402A cmt. k;
Edwards , 933 P.2d at 300 (stating that “the law regarding such products appears
at Comment k of the Restatement”).
Relying on Comment k, the Edwards court noted the exception to the
manufacturer’s duty to warn the ultimate consumer known as the “learned
intermediary doctrine”: where a product is properly prepared and marketed and
proper warning is given to the prescribing physicians, the manufacturer is
shielded from liability. Edwards , 933 P.2d at 300. “The reasoning behind this
rule is that the doctor acts as a learned intermediary between the patient and the
prescription drug manufacturer by assessing the medical risks in light of the
patient’s needs.” Id.
The Edwards court adopted the rationale cited by the Kansas Supreme Court
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when it adopted the learned intermediary doctrine:
Where a product is available only on prescription or through the
services of a physician, the physician acts as a ‘learned intermediary’
between the manufacturer or seller and the patient. It is his duty to
inform himself of the qualities and characteristics of those products
which he prescribes for or administers to or uses on his patients, and to
exercise independent judgment, taking into account his knowledge of
the patient as well as the product. The patient is expected to and, it
can be presumed, does place primary reliance upon that judgment. The
physician decides what facts should be told to the patient. Thus, if the
product is properly labeled and carries the necessary instructions and
warnings to fully apprize the physician of the proper procedures for use
and the dangers involved, the manufacturer may reasonably assume that
the physician will exercise the informed judgment thereby gained in
conjunction with his own independent learning, in the best interest of
the patient.
Edwards , 833 P.2d at 300-01 (emphasis added) (quoting Wooderson v. Ortho
Pharm. Corp. , 681 P.2d 1038, 1052 (1984) (applying Kansas law)). This rationale
applies to prescription drugs, because “the patient may obtain the drug only
through a physician’s prescription, and the use of prescription drugs is generally
monitored by a physician.” Id. at 301; see also Garside v. Osco Drug, Inc. , 976
F.2d 77, 80 (1st Cir. 1992) (applying Massachusetts law) (“The rationale
underlying the [learned intermediary doctrine] is that the prescribing physician, as
the ‘learned intermediary’ standing between the manufacturer and
consumer/patient, is generally in the best position to evaluate the potential risks
and benefits of ingesting a certain drug and to advise the patient accordingly.
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Under this doctrine, the manufacturer’s duty is fulfilled once it adequately warns
the physician.”).
Thus, in this case, the Ecks contend that Warner-Lambert had a duty to
adequately warn Dr. Rodgers, the prescribing physician, and Rugby had a duty to
adequately warn Dr. Newey, the treating physician, of the qualities and
characteristics of Dilantin and acetaminophen and of potential risks associated
with their concomitant use.
C. The Rebuttable Presumption under the Learned Intermediary Doctrine
Under Oklahoma law, the Ecks benefit from the development of a
rebuttable presumption in their favor:
[w]here a consumer, whose injury the manufacturer should have
reasonably foreseen, is injured by a product sold without a required
warning, a rebuttable presumption will arise that the consumer would
have read any warning provided by the manufacturer, and acted so as to
minimize the risks.
Cunningham v. Charles Pfizer & Co. , 532 P.2d 1377, 1382 (Okla. 1974)
(emphasis added) (quoting Reyes v. Wyeth Labs. , 498 F.2d 1264, 1281 (5th Cir.
1974) (applying Texas law)). The manufacturer warns the consumer, who is the
prescribing physician, who, in turn, acts as the learned intermediary. See Woulfe
v. Eli Lilly & Co. , 965 F. Supp. 1478, 1483 (E.D. Okla. 1997) (stating the
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Cunningham rebuttable “presumption . . . applies equally to the situation of
learned intermediaries”).
“In the duty to warn context, assuming that plaintiffs have established both
duty and a failure to warn, plaintiffs must further establish proximate causation by
showing that had defendant issued a proper warning to the learned intermediary,
he would have altered his behavior and the injury would have been avoided.”
Mazur v. Merck & Co. , 742 F. Supp. 239, 262 (E.D. Pa. 1990); see Thomas v.
Hoffman-LaRoche, Inc. , 949 F.2d 806, 812 (5th Cir. 1992) (applying Mississippi
law) (stating that “to create a jury question, the evidence introduced must be of
sufficient weight to establish, by the preponderance of the evidence, at least some
reasonable likelihood that an adequate warning would have prevented the plaintiff
from receiving the drug”). To inform the prescribing physicians of the potential
risks of an interaction during the concomitant use of acetaminophen and Dilantin,
Mr. Eck proposed that the following warning should have been included on both
products:
Phenytoin (generic name for Dilantin) may enhance the hepatoxicity
of acetaminophen secondary to enzyme induction and glutathione
depletion. Patients are advised to avoid concomitant use of
acetaminophen and phenytoin.
Aplt’s App. vol. III, doc. 31, at 2 (Dist. Ct. Order filed Jan. 18, 2000).
The district court apparently assumed without deciding that the Ecks
demonstrated that the manufacturer failed to warn of a non-obvious risk about
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which it knew or should have known, pursuant to Cunningham . Because the
adequacy of the proposed warning is irrelevant in light of Dr. Rogers’ testimony
discussed infra , we assume, for the limited purposes of this appeal, that the Ecks
are correct in their assertion that the defendants failed to warn the prescribing
physician of this risk. The Ecks thus receive the benefit of a rebuttable
presumption that an adequate warning “would have been read and heeded.”
Woulfe , 965 F. Supp. at 1483; cf. Van Buskirk , 760 F.2d at 493 (noting that
defendant may “defeat causation in a failure to warn case by discrediting
plaintiffs’ claims that . . . [the learned intermediary] . . . would have acted to
avoid” the injury).
Having established the presumption of causation-in-fact in the Ecks’ favor,
we must next determine whether the defendants, through the testimony of Drs.
Rodgers and Newey, have rebutted this presumption. The defendants may rebut
this presumption by establishing that although the prescribing physician would
have “read and heeded” the warning or additional information, this would not
have changed the prescribing physician’s course of treatment. See Woulfe , 965 F.
Supp. at 1485. The weight we afford to the physicians’ “testimony . . . depends
on the substance of the evidence as well as the credibility and reliability of the
treating physician[s].” Id.
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Assuming the defendants successfully rebut this presumption, the burden
shifts rather heavily back upon the Ecks. Our inquiry looks to whether the Ecks
“[came] forward with evidence sufficient to submit the case to a jury to determine
if [defendants’] alleged inadequate warning[s]” were a proximate cause of Mr.
Eck’s injuries. Id. at 1483; see also Garside , 976 F.2d at 81 (noting that “once
the presumption is rebutted, plaintiff must produce sufficient evidence to create a
triable issue on the question of causation”). To submit the case to a jury, the Ecks
must either discredit the physicians’ testimony or call into question the substance
of the testimony, or otherwise demonstrate that the alleged failure to warn was the
proximate cause of their injuries. Such a showing requires that the plaintiff
“demonstrate that the additional non-disclosed risk was sufficiently high that it
would have changed the treating physician’s decision to prescribe the product for
the plaintiff.” Thomas , 949 F.2d at 813 (applying Mississippi law); see also
Woulfe , 965 F. Supp. at 1485-86; In re Norplant Contraceptive Prods. Liability
Litig. , 955 F. Supp. 700, 710 (E.D. Tex. 1997) (where physician was aware of
dangers associated with drug and information that would have been provided in
warning would not have changed his decision to prescribe drug, court held no
causation), aff’d , 165 F.3d 374 (5th Cir. 1999).
III. DISCUSSION
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The Ecks contend that the district court made several errors when it granted
summary judgment to the defendants. First, they challenge the court’s decision to
focus primarily on the testimony given by Dr. Rodgers rather than also looking at
the testimony given by Dr. Newey. Second, they dispute that Dr. Rodgers’
testimony rebuts the presumption that she would have read and heeded a warning
about the interaction of Dilantin and acetaminophen. They also suggest that
because her testimony did not unequivocally indicate she had substantially the
same knowledge of the adverse risks that their proposed warnings would have
imparted, she could not properly evaluate the risks of the drugs’ interaction.
Finally, they point to disputed testimony as evidence that material issues of fact
regarding causation survived.
A. Dr. Newey
The Ecks first challenge the district court’s decision to limit its inquiry to
whether Dr. Rodgers would have prescribed Dilantin to Mr. Eck even if a warning
had been provided. The Ecks argue that the prescribing practices of Dr. Newey,
Mr. Eck’s treating physician, are also relevant, because the interaction of the
Isocet, prescribed by Dr. Newey, and the Dilantin, initially prescribed and later
monitored by him, were the cause of Mr. Eck’s injuries. Thus, the defendants
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must also establish that his practices would not have been altered with the
inclusion of a warning.
The Ecks emphasize that Dr. Newey testified that had he known of the
interaction between the two drugs, he would have passed this information on to
his patients. We acknowledge that Dr. Newey was the prescribing physician for
Isocet in January 1995, and also prescribed the loading dose of Dilantin to Mr.
Eck in February 1997, and continued to monitor his patient after Dr. Rodgers
resumed the prescribing physician role. However, it is undisputed that Mr. Eck
did not ingest the Isocet concomitantly with Dilantin until April 1997, when his
prescribing physician was Dr. Rodgers. There was no concomitant use of the
drugs when Isocet was originally prescribed, and there is no indication that in
1995 Mr. Eck was suffering from seizures that might require a Dilantin
prescription. That Dr. Newey might have heeded a warning to Mr. Eck about
possible adverse effects were he to prescribe Isocet to him in 1997 is of no
significance given the facts before us. We hold the district court did not err when
it focused exclusively on the testimony of Dr. Rodgers as the prescribing
physician.
B. Did Dr. Rodgers’ Testimony Rebut the Presumption?
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The Ecks next challenge whether the defendants presented evidence to
rebut the presumption that had Dr. Rodgers been properly warned, she would have
read and heeded the warning. The Ecks also question whether Dr. Rodgers’
knowledge about the adverse risks was substantially the same as the risks
presented in the proposed warning. If not, they posit, she would be unable to
incorporate the adverse risks into her risk/benefit analysis.
In rebutting the presumption, the defendants offer Dr. Rodgers’ deposition
testimony. Dr. Rodgers testified that she discussed with Mr. Eck the list of
medications he was taking, but does not recall that Isocet was on the list. She
stated that the Ecks assured her Mr. Eck was not taking any medications other
than those on the list. See Aplt’s App. vol. II, at 573 (depo. of Dr. Rodgers).
Dr. Rodgers also indicated that she had discussed Mr. Eck’s acetaminophen
intake with him. She told him that his intake of up to twelve tablets a day of
Tylenol was “way too much,” id. at 574, and indicated that she feared this intake
because “[acetaminophen] was hepatotoxic.” Id. She testified that Mr. Eck
indicated that he understood what “hepatotoxic” meant. Id.
Dr. Rodgers also testified that she was aware of medical literature that
suggested Dilantin might be a “enzyme inducer” that could increase the
hepatotoxicity of acetaminophen. She also testified that she was aware of the
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possibility of an adverse reaction when Dilantin and acetaminophen were taken
together. See id. at 574, 740.
Dr. Rodgers further testified that she performs a “risk/benefit analysis for
every medication.” Id. at 740. In weighing the risks and benefits, she concluded
that she would have prescribed Dilantin “even if [Mr. Eck] had been on a drug
that had a more frequent hepatotoxicity [than acetaminophen] . . . because the risk
of him having a problem due to his seizure was much greater than him taking the
Dilantin.” Id. at 736.
The Ecks argue that the evidence offered by defendants failed to rebut the
presumption that Dr. Rodgers would have read and heeded an adequate warning.
The Ecks dispute that Dr. Rodgers or any physician discussed with them Mr.
Eck’s acetaminophen use prior to his liver failure, and point out that Dr. Rodgers’
notes do not reflect such a discussion. See id. at 278, 731, 800. However, Mrs.
Eck does recall faxing a list of her husband’s prescriptions to Dr. Rodgers, and
that they discussed the medications he was taking. The Ecks also point to Dr.
Rodgers’ testimony that she generally does not “particularly find Tylenol to be
effective” and that it “has a number of things that make it less than an attractive
drug to use,” including its “potential for hepatotoxicity” as evidence that she
would have changed her course of treatment. Id. at 577.
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The Ecks construe Dr. Rodgers’ “heeding” an adequate warning to mean
she would have given the warning. However, “‘heed’ in this context means only
that the learned intermediary would have incorporated the ‘additional’ risk into
[her] decisional calculus.” Thomas , 949 F.2d at 814. In the risk/benefit analysis
of drug prescription, the prescribing physician “can choose to use the product and
face its risks, or choose not to use the product and lose its potential benefits.
Generally, using the product will present the less risky of these two alternatives.”
Id. at 813; see also Talley v. Danek Med., Inc. , 179 F.3d 154, 163 (4th Cir. 1999)
(applying Virginia law) (noting that “the prescribing physician can take into
account the propensities of the drug, as well as the susceptibilities of [her]
patient” and has “the task of weighing the benefits of any medication against its
potential dangers”).
We also disagree with the Ecks’ construction of the burden shifting under
the learned intermediary doctrine. Dr. Rodgers testified that even if she knew Mr.
Eck was taking a drug with a more frequent hepatotoxicity enzyme, she would
have still prescribed Dilantin to Mr. Eck . We hold the defendants provided
sufficient evidence that Dr. Rodgers would have not changed her course of
treatment. See Woulfe , 965 F. Supp. at 1485; Garside , 976 F.2d at 80 (“Where
the manufacturer fails to provide the physician with an adequate warning, courts
have held that the manufacturer may still be shielded from liability if it can show
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that the prescribing physician would not have heeded an adequate warning.”); see
also Plummer v. Lederle Labs. , 819 F.2d 349, 358-59 (2d Cir. 1987) (applying
California law) (granting judgment as a matter of law and noting that “the
plaintiff failed to prove that a proper warning would have altered the doctor’s
conduct”).
C. Did Dr. Rodgers have Substantially the Same Knowledge of
Adverse Risks that the Warning Would have Imparted?
The Ecks next propose that because Dr. Rodgers’ testimony did not imply
that she had substantially the same knowledge of the adverse risks as the proposed
warning would have reflected, her testimony did not demonstrate “unequivocally
that s/he knew at the relevant time all the information which would have been
included in a warning.” Garside , 976 F.2d at 82. Dr. Rodgers testified that she
was aware of a “scientific hypothesis” that the hepatotoxicity of acetaminophen is
increased when used in conjunction with Dilantin, but she did not appear certain
of the interaction between a therapeutic dose of acetaminophen and Dilantin.
Aplt’s App. vol. II, at 574, 740. Thus, she was unable to incorporate this
knowledge into her risk/benefit analysis of Mr. Eck’s course of treatment.
The Ecks cite Christopher v. Cutter Labs. , 53 F.3d 1184, 1192 (11th Cir.
1995) (applying Florida law) in support of their contention that Dr. Rodgers must
have unequivocal knowledge of the effects of the interaction of the drugs. In
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Christopher , the Eleventh Circuit examined whether the plaintiffs had presented
substantial evidence that absence of an adequate warning was a proximate cause
of the injury. The defendant manufacturer challenged a jury instruction that
required the jury to find that, at the time in question, the prescribing physician
had a knowledge of “reasonable evidence” of the connection between AIDS and
blood products. Id. at 1193. The given warning required only a knowledge that
the “possibility exists” that AIDS could be transmitted through blood products.
Id. There was no testimony that physicians in general or that the prescribing
physician understood that there was reasonable evidence of an association
between AIDS and blood products during the relevant timeframe. The Eleventh
Circuit held that the district court erred when it required the manufacturer to
establish “reasonable evidence” of the risk, which imposed “a higher and
erroneous layer of proof on its affirmative defense” and that the error required a
new trial. Id. at 1193.
In the present case, we are faced with a very different set of facts: Dr.
Rodgers has testified that she is aware that Dilantin is an enzyme inducer, one
that could increase the hepatotoxicity of acetaminophen. She also testified that
she was aware of the possibility of an adverse reaction when Dilantin and
acetaminophen were taken together. Most importantly, she testified that even if
she knew Mr. Eck was taking, or might take, a drug with a more frequent
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hepatoxicity enzyme than acetaminophen, she still would have prescribed
Dilantin, “because the risk of him having a problem due to his seizure was much
greater than him taking the Dilantin.” Aplt’s App. vol. II, at 736. See also
Thomas , 949 F.2d at 811-15 (holding that a warning stating that seizures had
occurred in 9 of 400,000 patients who had ingested the drug Accutane would not
have altered physician’s behavior where he testified that he was aware at the time
he prescribed the drug of “the possibility that Accutane may have caused seizures
in very rare cases”); Plummer , 819 F.2d at 358 (holding that where physician
testified he “was aware of the risks of contact polio,” a warning stating that an
unimmunized person should avoid contact with a polio vaccinee for 30 days
would not have altered his behavior); Stanback v. Parke, Davis & Co. , 657 F.2d
642, 645 (4th Cir. 1981) (applying Virginia law) (holding that a warning stating
that there was a risk of acquiring a neurological disorder from ingesting the drug
Fluogen would not have altered physician’s behavior where his “decisions and
actions [were] made in full knowledge of [that] information”); Windham v.
Wyeth Labs., Inc. , 786 F. Supp. 607, 612 (S.D. Miss.1992) (applying Mississippi
law) (holding that a warning stating that a pregnant patient who uses Phenergan
suppositories might suffer adverse consequences would not have altered
physician’s behavior where he testified that he was aware of such risk and
“weighed the risk of the drug against the benefit of the drug” before prescribing
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it). Cf. Garside , 976 F.2d at 82 (holding where physician’s affidavit stated he
was aware of “alleged connection” between the combined ingestion of
phenobarbital and amoxicillin and the risk of toxic epidermal necrolysis did not
suggest the physician knew of the causal connection).
Mr. Eck’s reliance on Tatum v. Schering Corp. , 795 F.2d 925, 927 (11th
Cir. 1996) (applying Alabama law), is similarly misplaced. There, as in Garside ,
the prescribing physician was not adequately warned of the degree or extent of
serious adverse effects. The Tatum court held that a jury might have concluded
the physician, armed with this knowledge, might have reconsidered her decision
to prescribe the drug. See id. Here, Dr. Rodgers testified that she still would
have prescribed Dilantin, because the risk of seizure was more severe than the
risk of hepatotoxicity induction. Thus, Dr. Rodgers was already aware of the
medical risk that the warning would have imparted, and having integrated this
knowledge into her risk/benefit calculation, determined her decision to prescribe
would remain unchanged. See e.g. , Garside , 976 F.2d at 80 (collecting cases and
stating “[w]here the manufacturer fails to provide the physician with an adequate
warning, courts have held that the manufacturer may still be shielded from
liability if it can show that the prescribing physician would not have heeded an
adequate warning . . . [and] have reasoned that the physician’s conduct acts as an
intervening-superseding cause of the plaintiff’s injury which vitiates any liability
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on the part of the manufacturer”); Stanback , 657 F.2d at 645-46 (stating that “the
manufacturer cannot be said to have caused the injury if the doctor already knew
of the medical risk”); Wooten v. Johnson & Johnson Prods, Inc. , 635 F. Supp.
799, 803 (N.D. Ill.1986) (noting that “[c]ourts have held consistently that a drug
manufacturer is entitled to summary judgment where the prescribing physician is
aware of the risks associated with a drug”) (citing Goodson v. Searle Labs. , 471
F. Supp. 546 (N.D. Conn. 1978), and Cobb v. Syntax Labs. , 444 So. 2d 203 (La.
App. 1983)).
Oklahoma courts have not considered whether a physician’s conduct
automatically acts as an intervening cause relieving the manufacturer of liability,
but instead shifts the burden back to the plaintiff to allow him to controvert the
physician’s testimony. See Woulfe , 965 F. Supp. at 1485-86. If the Ecks can
“produce sufficient evidence to create a triable issue of the question of
causation,” Garside , 976 F.2d at 81, they will defeat a motion for summary
judgment. See Woulfe , 965 F. Supp. at 1485-86 (noting plaintiff was unable to
establish that failure to warn was a proximate cause of injuries and granting
summary judgment to defendant).
D. Material Fact Questions Regarding Causation
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Finally, the Ecks contend that even if the defendants successfully rebutted
the presumption that a proper warning would have been heeded, they satisfied
their burden by presenting sufficient evidence to create a material fact as to
causation by casting doubt upon the credibility of Dr. Rodgers. Ordinarily, what
constitutes the proximate cause of any injury is a question of fact. See Lefthand
v. City of Okmulgee , 968 P.2d 1224, 1226 (Okla. 1998). “However, the question
of proximate cause becomes a question of law when the facts are undisputed and
there is no evidence from which a jury could reasonably find a causal connection
between the allegedly negligent act and the injury.” Id.
The Ecks challenge Dr. Rodgers’ credibility, and note that she formerly
conducted research for several pharmaceutical companies. As the district court
observed:
These facts standing alone, however, merely offer speculation as to Dr.
Rodgers’ motives for testifying and they are clearly insufficient to call
into question either Dr. Rodgers’ credibility or the veracity of her
statements.
Aplt’s App. vol. III, doc. 31, at 8 (Dist. Ct. Order filed Jan. 18, 2000). The
speculative nature of this argument is increased by the fact that if anything, Dr.
Rodgers’ testimony would have enhanced her own exposure to liability. Absent
evidence suggesting Dr. Rodgers was otherwise influenced by the defendants, we,
like the district court, find no reason to question her credibility or the truth of her
testimony.
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Even viewing the facts most favorably to the Ecks, we cannot disagree
with the district court’s conclusion that Dr. Rodgers would have prescribed
Dilantin no matter how carefully the Ecks proposed or refined the phrasing of the
suggested warning. Dr. Rodgers testified about her independent knowledge of the
risk of the potential interaction between the two drugs, and indicated that if
presented with even a higher risk, she would have prescribed Dilantin. The Ecks
have failed to controvert this testimony and have failed to create an issue of fact
of whether defendants’ failure to warn was the proximate cause of their injuries.
IV. CONCLUSION
We agree with the district court that the Ecks are unable to demonstrate that
a warning would have changed Dr. Rodgers’ or Dr. Newey’s behavior at the time
of prescribing Dilantin and Isocet, respectively. The Ecks are, in turn, unable to
establish that the alleged failure to warn of the possible adverse reactions between
the drugs was the proximate cause of Mr. Eck’s injuries. Accordingly, we
AFFIRM the district court’s grant of summary judgment to defendants.
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