Synthetic Cannabinoids: Can These Drugs Give Rise to a Real Products Liability Claim?

Synthetic Cannabinoids: Can These Drugs Give Rise to a Real Products Liability Claim? Tuesday, May 30, 2017

Author: Daniel L. Marks


            Synthetic cannabinoids, “commonly known as ‘synthetic marijuana,’ ‘K2,’ or ‘Spice,’”[1] are a relatively new method of getting high.  The term “synthetic cannabinoids” refer[s] to a growing number of man-made, mind-altering chemicals that are either sprayed on dried, shredded plant material so they can be smoked (herbal incense) or sold as liquids to be vaporized and inhaled in e-cigarettes and other devices (liquid incense).”[2]  These substances are called cannabinoids because the chemicals sprayed on the herbs are similar to tetrahydrocannabinol (THC), the primary psychoactive ingredient in marijuana.[3]  Synthetic cannabinoids, however, “bind to the cannabinoid receptors in the brain more tightly than THC itself, which often leads to powerful and unpredictable effects, such as severe episodes of acute psychotic effects.”[4]

      Synthetic cannabinoids are “mixed by chemists in labs.”[5]  The purpose is to create chemical compounds designed to mimic the effects of naturally occurring drugs like marijuana . . . while staying just inside the law. Because the newest compounds do . . . [not] yet appear on state and federal lists of illegal drugs, the sellers can market them as legal. As soon as authorities add a compound to the prohibited list, the chemists tweak the formula—ever so slightly—to make a new substance that purports to be legal.[6]

      Synthetic cannabinoids “are often sold in legal retail outlets as ‘herbal incense;’ or ‘potpourri.’”[7]  They also are available for purchase online.[8]  These products are sold “in colorful foil packages and sell similar liquid incense products, like other e-cigarette fluids, in plastic bottles.  They are marketed under a wide variety of specific brand names[.] . . . Hundreds of . . . brand names now exist.”[9]  Additionally, the substances “are marketed in packages boasting cartoon characters and catchy names designed to appear harmless as well as alluring.”[10]  And “because of the similarity to the chemicals found in the marijuana plant . . . they are often marketed as ‘safe,’ legal alternatives to that drug.”[11]  This is because people tend to equate ‘herbal’ with ‘safe.’”[12]  However, despite labels that often claim they contain “natural” material taken from a variety of plants, “the only parts of these products that are natural are the dried plant materials.”[13]

      This paper gives a brief description of consumer interactions with synthetic cannabinoids, and the regulatory reaction to their emergence.  It then describes various theories in which an individual could bring a products liability claim for synthetic cannabinoids.  Its primary focus is whether the warning label (“not for human consumption”) found on synthetic cannabinoid packaging is a sufficient warning.  This paper will also examine the manufacturer’s possible defenses. 


a.         Health Effects of Using Synthetic Cannabinoids

     The health effects of synthetic cannabinoids have just begun to be the subject of study due to their recent emergence and labeling.  The products are often labeled “not for human consumption” which permits manufacturers “to mask their intended purpose and avoid Food and Drug Administration (FDA) regulatory oversight of the manufacturing process.”[14]  However, these warning labels are often small, as some of the containers are sold with as little as 1.5 grams of product inside.[15]  There is a short warning on “” webpage:

Warning! K2 Incense is not for human consumption. Those that have reported taking K2 orally have seen side effects of headaches, vomiting, congested lungs, Sinus [sic.] congestion, tachycardia, paranoia, psychotic episodes and similar side effects to marijuana (weed). Please avoid any suppliers that inform you that these practice [sic.], either to smoke or digest K2, is normal use of our incense.[16]

 The website’s short warning is followed by four paragraphs that claim the benefits of the “incense.”[17]  Note that the website does not warn of smoking synthetic cannabinoids, it just warns of taking it “orally.”

            Despite a label that states synthetic cannabinoids are “not for human consumption,” use of the drug is extremely popular among young people.  “According to the 2012 Monitoring the Future survey of youth drug-use trends, one in nine 12th graders in America reported using synthetic cannabinoids in the past year.  This rate, unchanged from 2011, puts synthetic cannabinoids as the second most frequently used illegal drug among high school seniors after marijuana.”[18]  This is likely because synthetic cannabinoids are easily accessible and “standard drug tests cannot easily detect many of the chemicals used in these products.”[19]   Additionally, the synthetic drugs can be “up to 1,000 times stronger binding to cannabis receptors when compared to traditional marijuana.”[20]  

            Due to the infancy of synthetic cannabinoids, there is “little medical research on th[e] . . . compounds [and] their precise effect is not well understood.”[21]  Despite the long-term impacts of using synthetic cannabinoids being unknown, alarming short-term effects have been reported by substance abuse specialists and emergency room personnel.  Specifically, “[t]he effects of synthetic cannabinoids include severe agitation and anxiety, nausea, vomiting, tachycardia (fast racing heartbeat), elevated blood pressure, tremors and seizures, hallucinations, dilated pupils, and suicidal and other harmful thoughts and/or actions.”[22]  “Medical experts caution that a single dose of a synthetic cannabinoid can be hazardous because of the crude way in which producers spray the chemicals onto . . . plant material that is . . . smoked. If the cannabinoid is sprayed unevenly, it can create hot spots where the concentration of the chemical is dangerously high.”[23]  The result is that one hit of a synthetic cannabinoid can be different from the next.  This led one commentator to state, “you hypothetically could use the same brand today and smoke it and get high. And use the same brand tomorrow, smoke it and it could be fatal.”[24]

     Without carefully controlled studies, it is hard to know how typical any individual reaction to synthetic cannabinoid use is.  However, as a result of synthetic cannabinoids’ popularity and potency, there has been no shortage of adverse reactions to it.  In 2010, for example, “more than 11,000 American emergency room visits were tied to synthetic cannabinoids.[25]  Not all of those emergency room visits ended with the patient being discharged.  In Florida, “synthetic marijuana was listed as the cause of six deaths from January to June 2013.”[26]  Unfortunately, most individuals that wound up in the emergency room were children ages 12-17, and their stories are eye-opening.[27] A California teenager named Connor Eckhardt recently died after taking only one hit of the pot-like substance in 2014.[28]  Another example, Emily Bauer—a sixteen year-old from Houston—ended up in the ICU after buying “potpourri” with her friends at a gas station.[29]  “Emily complained of a migraine and took a nap” after smoking synthetic cannabinoids with her friends.[30]  She woke up a different person; stumbling and slurring her words, she morphed into a psychotic state of hallucinations and violent outbursts.[31]  After being rushed to the hospital by paramedics, Emily had to be strapped down into her bed because she bit guardrails and attempted to bite those trying to help her.[32]  Eventually, doctors placed Emily into a medically induced a coma for her own safety.[33] Later, “an MRI revealed she had suffered several severe strokes.”[34]  The synthetic cannabinoids destroyed a large portion of her brain.[35]  Nine months after the incident, Emily returned to school, albeit a much different young woman.[36]  She is now partially blind, unable to read and write, and paralyzed, leaving her wheelchair bound.[37]  Emily’s stepfather told the media: “I’d never have thought we’d be in this situation. If she had bought it off the street or from a corner, that’s one thing, but she bought it from a convenience store.”[38]  While more study is warranted, reports like these raise legitimate and serious concerns about the dangers associated with synthetic cannabinoids.

b.         The Legislative Response to the Development of Synthetic Cannabinoids

     The popularity of synthetic cannabinoids and the numerous adverse reactions to it have forced States and the Federal government to act quickly.  Prior to 2010, “synthetic cannabinoids were not controlled by any State or at the Federal level.”[39]  Now, “all 50 states have banned . . . synthetic drugs.”[40]  Initially, state legislative action targeted specific versions of these drugs with individual bans.  However, minor changes to the chemical composition of these substances can create new, but very similar, drugs not previously covered by law. In response, legislation in subsequent years has been more general in nature, targeting entire classes of substances or using broad language to describe the prohibited drugs. The intent of general bans is to prevent new forms of synthetic drugs from remaining unregulated, while still allowing use for approved medical and research purposes.[41]

     The Federal government has also taken action against synthetic drugs.  For instance, “[o]n Tuesday, March 1, 2011, [the Drug Enforcement Agency] published a final order in the Federal Register temporarily placing five synthetic cannabinoids into Schedule 1 of the [Controlled Substance Act].  The order became effective on March 1, 2011.”[42] Additionally, President Obama signed into law the Synthetic Drug Abuse Prevention Act, which is part of the FDA Safety and Innovation Act of 2012.  “The law permanently places 26 types of synthetic cannabinoids and cathinones[43] into Schedule I of the Controlled Substances Act (CSA).”[44]  Further, “[t]he Controlled Substance Analogue Enforcement Act of 1986 allows many synthetic drugs to be treated as controlled substances if they are proven to be chemically and/or pharmacologically similar to a Schedule I or Schedule II controlled substance.”[45]

            The general bans, however, have not solved the issue.  “Chemists motivated by heavy profits have still been able to alter substances . . . faster than the substances can be scheduled.”[46]  Since “the newest compounds do . . . [not] yet appear on state and federal lists of illegal drugs,       . . . sellers can market them as legal.  As soon as authorities add a compound to the prohibited list, the chemists tweak the formula—ever so slightly—to make a new substance that purports to be legal.”[47]  Thus, despite the risks involved to both the manufacturer and consumer, synthetic cannabinoids are still widely available.


a.         Theories of a Product Liability Claim

     The warning label that synthetic cannabinoids are “not for human consumption” is intended to help manufacturers avoid liability for the use of their products. A traditional principle of “products liability law is that a manufacturer or supplier of goods has a duty to warn of any danger from the unintended or unintended but reasonably foreseeable use of its products.”[48]  Even when a warning is provided, “a manufacturer may still be liable if the warning is not deemed to be legally ‘adequate.’”[49]  For the sake of this analysis, this paper assumes the plaintiff consumed synthetic cannabinoids with a label stating “not for human consumption” and suffered an injury as a result.

     A product is considered defective when, “at the time of sale or distribution, it contains a manufacturing defect, is defective in design or is defective because of inadequate instructions or warnings.”[50]  A product’s warnings are inadequate “when the foreseeable risks of harm posed by the product could have been reduced or avoided by the provision of reasonable . . . warnings by the seller . . . and the omission of the . . . warnings renders the product not reasonably safe.”[51]  Thus, the issue in a synthetic cannabinoid warning claim “is whether the cautionary language of ‘not for human consumption’ constitutes an adequate warning in light of the foreseeable use and user of the product.”[52] 

     Failure to warn claims “can be brought under either negligence or strict liability theories. The strict liability theory focuses on the condition of the product itself; whereas the negligence theory looks to the reasonableness of the manufacturer’s failure to warn adequately.”[53]  Although both causes of action have different requirements, “much has been written, by both courts and commentators, about whether there is any meaningful difference between the strict liability failure-to-warn and negligent failure-to-warn causes of action.”[54]  Thus, “[t]he distinction between the two theories of liability is questionable.”[55]

     Most courts hold “that a manufacturer is under a duty to warn of dangers presented by any product if the absence of a warning would render the product unreasonably dangerous.”[56]  “[I]n strict liability cases, [the] manufacturers’ knowledge of product dangers is assumed or imputed.”[57]  Despite the title of “strict liability,” many jurisdictions have determined that foreseeability is an element of strict liability and “require[s] [that] the manufacturer have actual or constructive knowledge of the risk of injury in order to be strictly liable for failing to warn.  This requirement frees manufacturers from liability for injuries resulting from unknown or unknowable risks.”[58]  The plaintiff must prove the “defendant did not adequately warn of a particular risk that was known or knowable in in light of the generally recognized and prevailing best scientific and medical knowledge available at the time of manufacture.”[59]

             The issue is whether a warning label stating “not for human consumption” adequately warns users of a particular risk that was known or knowable in light of the generally recognized and prevailing best scientific and medical knowledge available at the time of manufacture.  It is difficult to see how a synthetic cannabinoid manufacturer could be ignorant of the risk that its consumers might be injured.  Perhaps a manufacturer could claim ignorance when the product was first produced, but now it is impossible to claim ignorance.  Manufacturers are aware of the adverse reactions to smoking synthetic cannabinoids given the extensive news coverage of illness and death related to their use. Manufacturers also are on notice because of the State and Federal government’s efforts to ban the substance.  Manufacturers would likely claim they were unaware of the harmful effects of a specific chemical formulation when it was first released into the market, since the synthetic cannabinoids’ formula is ever-changing.  This, however, is unlikely to succeed given that the new formulations consist of minor changes and one could reasonably expect adverse reactions to continue when the new chemical formula is similar to the old formula.

            “Not for human consumption” is likely inadequate to impress the consumer of the risks involved with using the product.  Thus, it probably will not satisfy the manufacturer’s duty to warn.  “Not for human consumption” is short, broad, and ambiguous.  Consumption has a variety of meanings; for instance, Merriam-Webster defines “consume” as “3(a): to eat or drink especially in great quantity.”[60]  Merriam-Webster’s definition of “consume” is not equivalent to “smoke.”  A plaintiff in a products liability suit against a synthetic cannabinoid manufacturer could misinterpret “consumption” to mean “do not eat this product.”  Since eating and smoking are different, the warning label is not likely to impress the consumer of the dangers of smoking synthetic cannabinoids.  Thus, given the ambiguous nature of the warning label’s words, it does not adequately warn of the product’s dangers if smoked.

     Additionally, the warning label could easily be improved.  It would be best served if accompanied by a skull and crossbones to impress the consumer of the dangers of synthetic cannabinoids.  This symbol would universally indicate the product is not meant to be ingested through eating, smoking, drinking, etc.

            If a plaintiff chooses a negligence theory instead of strict liability, he or she “must prove the following elements: the manufacturer owed a duty to warn of some danger associated with the foreseeable use of the product, the manufacturer breached that duty, and the breach was the proximate cause of the plaintiff’s injuries.”[61]  The duty to warn has two components.  First, the manufacturer has a duty to warn of foreseeable dangers inherent in the product.  Second, the manufacturer has a duty to provide adequate instructions for safe use.  “If both the particular use of the product and the associated injury were reasonably foreseeable by the manufacturer of the alleged defective product, then a duty to warn has been established.”[62]  One can prove the manufacturer breached its duty by demonstrating the manufacturer failed to warn or the warning did not adequately communicate the risk of harm.  “It is clear the duty has been breached when a manufacturer fails to provide a warning, but the harder question involves assessing the adequacy of a manufacturer’s warning.”[63]

            Similar to a failure to warn claim under the strict liability analysis, the manufacturer’s warning label is likely insufficient under the negligence theory.  Given that manufacturers know, or reasonably should know, of the risks of smoking synthetic cannabinoids, the manufacturers have a duty to inform the consumers of the dangers from that foreseeable use.  Even though the manufacturers claim their products are not intended to be smoked, that is largely irrelevant under the negligence theory.  Under the negligence theory, what is relevant is that there is a warning of the dangers of a reasonably foreseeable use.[64]  Smoking synthetic cannabinoids are a reasonably foreseeable use of the product, given that it is sold in smoke shops, the various reports of illness and death after people have smoked the product, and because the State and Federal government’s efforts to ban the substance.

            The next issue is whether the warning label is sufficient.  Although this is ultimately a question for a jury to decide, the “not for human consumption” warning label is likely insufficient to impress the consumer of the dangers associated with the product for several reasons.  First, it does not mention any of the possible side effects if it is smoked.  As previously discussed, this is a common enough use that should be addressed explicitly.  Second, the common definition of “consumption” in the warning label is too ambiguous even if an explicit warning about smoking the products is not warranted.  As explained in the strict liability section, Merriam-Webster’s definition of “consume” does not mean “smoke.”  Since eating and smoking are different, the warning label is not likely to warn the consumer of the dangers of smoking synthetic cannabinoids.  Finally, the warning label is likely inadequate is because it fails the risk-utility balancing analysis since it could be easily improved.[65]  The label would be best served if accompanied by a skull and crossbones to impress the consumer of the dangers of synthetic cannabinoids.  This symbol would indicate the product is deadly, regardless of how it is ingested.

     Once the plaintiff has established “the manufacturer did not adequately warn of a product’s dangers, the plaintiff must still prove proximate causation.”[66]  Proximate causation must be proven in both strict-liability and negligence actions.  “Proximate cause in strict liability cases embodies two concepts: cause-in-fact and proximate (or legal) cause. Cause-in-fact is essentially ‘but-for’ analysis, looking at the manufacturer’s conduct and the event resulting in injury.”[67]  Proximate cause is “any cause which in natural and continuous sequence, unbroken by any efficient intervening cause, produces the injury complained of and without which the result would not have occurred.”[68]  “Plaintiffs often have difficulty proving that warnings would have caused them to alter their behavior or conduct, thus avoiding injury.  For this reason, proximate cause is known as the ‘plaintiff’s Achilles heel’ in warning cases.”[69]

       After the “plaintiff proves that the lack of a warning rendered a product unreasonably dangerous or defective, the plaintiff benefits from a presumption that had a warning been given, it would have been heeded.”[70]  The Restatement (Second) of Torts, Section 402A comment j, states: “[w]here warning is given, the seller may reasonably assume that it will be read and heeded; and a product bearing such a warning, which is safe for use if it is followed, is not in defective condition, nor is it unreasonably dangerous.”[71]  “The plaintiff then must connect the manufacturer’s inadequate warning and the claimed injuries and must prove further that had an adequate warning been given, he would have altered his behavior or conduct so as to avoid injury.”[72]

      Despite the heeding presumption, “the manufacturer’s failure to warn need not be the sole proximate cause; rather, it must be a substantial factor or an efficient causal agent. A manufacturer may overcome a plaintiff’s claim that an absent or inadequate warning proximately caused injury” in two different ways.[73]  First, the manufacturer can show that the plaintiff would have acted or behaved in the same manner if an adequate warning was present.  Second, the manufacturer can prove “that a third party’s independent or intervening acts proximately caused the injury.  Manufacturers frequently prevail on the first point when there is evidence that the plaintiff or decedent did not read the warning.”[74]

      The plaintiff will have the greatest difficulty proving proximate causation.  Usually, “once a plaintiff proves that the lack of a warning rendered a product unreasonably dangerous or defective, the plaintiff benefits from a presumption that had a warning been given, it would have been heeded.”[75]  However, in this case a plaintiff must overcome the fact that he did not follow an existing warning label’s instructions.[76]  The plaintiff must prove to the jury that a different warning would have caused him to alter his behavior or conduct, thus avoiding injury.  Perhaps a different warning label that says “do not smoke” or, alternatively, one with a skull and crossbones symbol on it would prevent a plaintiff from smoking the product.  Ultimately, this could be a tough argument for the plaintiff, and the case would turn on whether the plaintiff can show he or she would have followed a better instruction.

b.         Defenses to a Products Liability Claim

            In the event a plaintiff is able to show the warning label is inadequate, manufacturers may have several viable defenses available.  The first of those defenses is that manufacturers have no obligation “to warn of hazards that are obvious to ordinary consumers, a basic principle that is known as the ‘obvious danger rule.’”[77]  Consistent with that rule, “manufacturers generally need not warn persons about [obvious] hazards [or hazards] already known to them.”[78]  The obviousness of a danger is not dependent upon the user’s actual knowledge.  “Rather, the danger must be so obvious that it would be unreasonable to impose a duty to warn on the manufacturer. The danger must be sufficiently apparent that a user ‘would appreciate the danger to the same extent that a warning would provide.’”[79]  As Professor Prosser stated, there is no duty to warn that “a knife or an ax will cut, a match will take fire, dynamite will explode, or a hammer may mash a finger.”[80]

      The obvious danger rule is not applied as straightforwardly as it may seem, however.  For instance, in Fleck v. KDI Sylvan Pools Inc., the plaintiff was injured when he dove into a shallow, above-ground swimming pool and struck his head on the bottom. [81]  The pool’s liner contained neither “no diving” warnings nor depth markers.[82]  The manufacturer claimed diving into water of unknown depth constituted an open and obvious hazard.[83]  “The plaintiff testified that the pool looked deep and if the pool contained warnings or depth markers, he would have not dived into the pool.  The court concluded that the danger posed by diving into the pool was not open and obvious.”[84]  Although “Fleck appears to be a questionable decision, and courts generally hold that diving into shallow water and other reckless poolside conduct pose obvious dangers,”[85] Fleck demonstrates how a plaintiff can prove a danger is not obvious.

       Unfortunately for the manufacturer, the risks of smoking synthetic cannabinoids may be less obvious than the risks of diving into a shallow pool.  While the American public generally knows smoking is unhealthy, it might not be obvious to a reasonable individual that he or she could suffer from serious side effects, such as vomiting, strokes, or death, after smoking synthetic cannabinoids one time.  Further, given the inconsistency of chemical concentration on the herbs, it is less likely that the risk would be obvious each time a consumer smoked it, since one hit of a synthetic cannabinoid can be different from the next.  Thus, this defense might be unsuccessful for the manufacturer.

            The second possible defense a synthetic cannabinoids manufacturer can assert is the assumption of risk defense.  To use assumption of risk as a defense, the “defendant must establish that the plaintiff knew of the presence of the risk, understood its nature, and voluntarily chose to accept it.”[86]  While synthetic cannabinoid consumers may not know of every health risk from the label, a reasonable consumer likely knows that smoking is unhealthy.  The manufacturer would argue that by smoking the product, the consumer voluntarily chose to accept the risks of smoking it.  The consumer, however, would argue that he assumed the reasonable risks of smoking, such as the adverse health consequences that arise after years of smoking, not the risk of an immediate, adverse reaction.  Since synthetic cannabinoids are much stronger than marijuana and can have an immediate impact on the user’s health, unlike cigarettes, will the user be able to fully appreciate the risk of smoking synthetic cannabinoids?  Given the relative infancy of the drug, it is unlikely that a reasonable consumer could appreciate the full risk involved.  The manufacturer, however, could note that once the consumer has tried the drug, the consumer can appreciate the quick-acting effects of the drug and recognize the risks involved.  The plaintiff would argue that he or she could not appreciate all of the risks since the synthetic cannabinoids are inconsistently sprayed, which might conceal the strongest effects until one smoked the part of the product onto which more of the drug had been sprayed.

      The manufacturer also could rely on its warning label that the product is “not meant for human consumption.”  The manufacturer would argue the consumer relied upon it given the Restatement’s presumption that the consumer will heed a warning.[87]  By not following the warning, the manufacturer would argue the consumer assumed the possible risks when he consumed the product, regardless of whether he knew of all possible risks.  Again, the consumer would argue that he interpreted “consumption” to mean something different than smoking and was not aware of the precise risks involved.  This would be an issue for the jury to decide.

            Finally, the manufacturer could also raise the defense of product misuse.  “Given temporal meaning, ‘misuse’ is the use of a product in a way that the manufacturer did not intend it to be used.”[88]  However, as one Seventh Circuit opinion stated, “Americans are not Prussians—they are not schooled to obedience as the prime virtue of the good citizen—so they are constantly putting things to new uses.”[89]

            In products liability, one misuses a product when it is used for a purpose that was neither intended nor reasonably foreseeable by the manufacturer.  A manufacturer may be liable for foreseeable misuse of its products and foreseeable product alterations.  Thus, “[a] manufacturer must warn of dangers associated with foreseeable misuse. On the other hand, an unforeseen misuse of a product will not expose a manufacturer to liability.  Whether an unintended product use is foreseeable is measured against an objective standard.”[90]

            The product misuse defense will likely be unsuccessful for the manufacturer.  Although the warning label instructs the consumer that the product is “not for human consumption,” the manufacturers are on notice that smoking the product is one popular (perhaps the only) use of it.  In fact, smoking the product is likely the manufacturer’s intended use of it.  Why else would the manufacturer sell 1.5 grams of herbs sprayed with synthetic cannabinoid chemicals for upwards of $10?  (If the manufacturer actually wanted to sell “incense” or “potpourri,” it could easily be produced without using complex chemical formulations that mimic THC).  That aside, even if smoking synthetic cannabinoids is misuse of the product, there is nothing to alert the consumer of that specific use.  The warning label states it is “not for human consumption.”  As indicated in the strict liability and negligence sections, “consumption” is ambiguous, and a reasonable person could interpret “not for human consumption” to mean that humans should not eat the herbs as if they were lettuce.

           Given the obviousness that users smoke the product, manufacturers could take very easy steps to utilize the product misuse defense.  For instance, if the manufacturer wrote a more specific warning label that would warn the consumer of specific risks of smoking the product, the product misuse doctrine should work.  For example, if the manufacturer warned: “This product is not meant for human consumption. Do not smoke, eat, or drink the product” and/or attached images to the packaging that indicated the product should not be smoked (no-smoking symbol) and that it is deadly (skull and crossbones symbol), the product misuse defense should work.


            The warning label on synthetic cannabinoids’ packaging that reads “not for human consumption” is inadequate to impress upon a consumer the risks of smoking the product.  If a consumer brings a products liability claim for failure to warn, the consumer is likely to be successful under either a strict liability or negligence theory.  The consumer will have difficulty showing the proximate cause of the injury.  The consumer must prove to the jury that a different warning would have caused the him to alter his behavior or conduct, thus avoiding injury.  This might be a losing point for the consumer.  It would be difficult to show that the consumer would follow a new warning when he disregarded a warning that the product is “not for human consumption.”  If the consumer establishes proximate causation, the manufacturer has several defenses available, although no defense will clearly eliminate possible liability.  The manufacturer’s best defenses are product misuse and assumption of risk.  Of course, the jury will decide whether there is liability.

 Preferred Citation Format:  Daniel L. Marks, Synthetic Cannabinoids: Can These Drugs Give Rise to a Real Products Liability Claim?, Neb. L. Rev. Bull. 1 (2017).

[1]  Synthetic Drugs (A.K.A. K2, Spice, Bath Salts, etc.), Office of National Drug Control Policy, (last visited Apr. 13, 2016).

[2]  What are Synthetic Cannabinoids?, National Institute on Drug Abuse, (last updated Nov. 2015),

[3]  K2 or Spice Drug Fact Sheet, Drug Enforcement Agency, (last visited Apr. 13, 2016).

[4]  Designer Drugs Lead to Designer Legislation, National Association of Attorney Generals (Fed. 28, 2014),

[5]  Eliza Gray, The Rise of Fake Pot, U.S. Senator Amy Klobuchar (Apr. 14, 2014),

[6]  Id.

[7]  Synthetic Drugs (A.K.A. K2, Spice, Bath Salts, etc.), supra note 1.

[8]  See, e.g., Buy K2 Incense,, (last visited Nov. 6, 2016).

[9]  What are Synthetic Cannabinoids?, supra note 2.

[10]  Teresa Stepzinski, Despite Playful Packaging Designed To Attract Teens, Synthetic Drugs Contain Real Danger, Jacksonville News (Oct. 3, 2015),

[11]  What are Synthetic Cannabinoids?, supra note 2.

[12]  Sam Eifling, Synthetic Marijuana: What Is It, And Is It Riskier Than Regular Pot?, (Apr. 16, 2013),

[13]  What are Synthetic Cannabinoids?, supra note 2.

[14]  Synthetic Drugs (A.K.A. K2, Spice, Bath Salts, etc.), supra note 1.

[15]  See, e.g., Bizarro 1.5 Gr., Organic Spice Blend, (last visited Nov. 6, 2016).

[16]  K2 Side Effects,, (last visited Nov. 6, 2016).

[17]  Id.

[18]  Id.

[19]  What are Synthetic Cannabinoids?, supra note 2.

[20]  Lu Parker, Parents Warn Against Synthetic Marijuana After 19-Year-Old Son Dies, KTLA 5 (last updated Aug. 8, 2015), (quoting Dr. Andrew Monte, the lead author of an editorial in the New England Journal of Medicine).

[21]  Gray, supra note 5.

[22]  Synthetic Drugs (A.K.A. K2, Spice, Bath Salts, etc.), supra note 1.

[23]  Gray, supra note 5.

[24]  Stepzinski, supra note 10.

[25]  Eifling, supra note 12.

[26]  Stepzinski, supra note 10.

[27]  Christina Zdanowicz, Teen Narrowly Escapes Death After Smoking Synthetic Marijuana, (last updated Feb. 5, 2013 at 4:28 PM),

[28]  Parker, supra note 20.

[29]  Zdanowicz, supra note 27.

[30]  Id.

[31]  Id.

[32]  Id.

[33]  Id.

[34]  Id.

[35]  Id.

[36]  Christina Zdanowicz, Teen Makes Dramatic Recovery After Smoking Synthetic Marijuana,, (last updated Sep. 11, 2013 at 10:48 AM). 

[37]  Id.

[38]  Zdanowicz, Teen Narrowly Escapes Death, supra note 27.

[39]  Synthetic Drugs (A.K.A. K2, Spice, Bath Salts, etc.), supra note 1.

[40]  Synthetic Drug Threats, National Conference of State Legislatures (Jan. 13, 2015),

[41]  Id.

[42]  K2 or Spice Drug Fact Sheet, supra note 3.

[43]  Cathinones are also known as bath salts, a synthetic drug that this paper does not cover.

[44]  Synthetic Drugs (A.K.A. K2, Spice, Bath Salts, etc.), supra note 1. 

[45]  Id.  

[46]  Designer Drugs Lead to Designer Legislation, National Association of Attorney Generals (Fed. 28, 2014),

[47]  Gray, supra note 5.

[48]  Matthew W. Adams & Kenneth Ross, Legally Adequate Warning Labels: A Conundrum for Every Manufacturer, For The Defense, (Oct. 1998),

[49]  Id.

[50]  Restatement (Third) of Torts § 2 (1998).

[51]  Id. at § 2(c).

[52]  Scarlett Steuart, Products Liability Action Against Manufacturers and Retailers of Synthetic Marijuana In Kentucky, The Kentucky Journal (Feb. 14, 2014),

[53]  Tyler Tassone, Should Metal Baseball Bats Come with A Warning Label? Assessing Failure to Warn Claims Before and After Enactment of the BBCOR Baseball Bat Performance Standard, 20 Sports Law. J. 211, 224 (2013).

[54]  Hildy Bowbeer, Wendy F. Lumish, & Jeffrey A. Cohen, Warning! Failure to Read This Article May Be Hazardous to Your Failure to Warn Defense, 27 Wm. Mitchell L. Rev. 439, 442 (2000).

[55]  Tassone, supra note 53, at 225.

[56]  Id. at 224.

[57]  Douglas R. Richmond, Renewed Look at the Duty to Warn and Affirmative Defenses; Duty to Warn Allegations Are Easy to Make, and the Cases Are Proliferating, Making It Time to Sharpen Up on the Affirmative Defenses, 61 Def. Couns. J. 205, 208 (1994).

[58]  Tassone, supra note 53, at 226 (quoting Restatement (Second) of Torts §402(A) cmt. j (1965)).  

[59]  Id.  

[60]  “Consume,” Merriam-Webster Online Dictionary, (last visited Nov. 6, 2016).

[61]  Tassone, supra note 53, at 227.

[62]  Id.

[63]  Id.

[64] See Wheeler v. John Deere Co., 935 F.2d 1090, 1104 (10th Cir. 1991) (holding that “[u]nder Kansas law, a manufacturer can be held liable for the foreseeable misuse of its product”); Kerns v. Engelke, 76 Ill. 2d 154, 165, 390 N.E.2d 859, 864 (1979) (holding that “[i]f the use of a product ‘is abnormal, but nonetheless one that may be anticipated, it may be foreseeable.’ There ‘is a distinction between the intended use and the foreseeable use, and where a particular use should be known to the reasonably prudent manufacturer such use cannot be labelled unforeseeable.’”) (citations omitted).

[65]  Adams & Ross, supra note 48, at 10 (noting that“[o]ne factor used when evaluating feasibility and cost is the burden imposed on the manufacturer. See Oman [v. Johns-Manville Corp.], 764 F.2d at 233 [(4th Cir. 1985)]. Where the burden of providing improved or additional warnings is low, a court is more likely to perceive that the actual warning provided is inadequate.”).

[66]  Tassone, supra note 53, at 229.

[67]  Richmond, supra note 57, at 213–14.

[68]  1 Modern Tort Law: Liability and Litigation § 4:4 (2d ed.). 

[69]  Richmond, supra note 57, at 214.

[70]  Id.  

[71]  Restatement (Second) of Torts, Section 402A cmt. j (1965).

[72]  Richmond, supra note 57, at 214.

[73]  Id.

[74]  Id.

[75]  Id.

[76] Unless the word “consumption” is understood to refer only to eating or drinking, because a plaintiff who smokes the product has followed a warning not to eat or drink it. 

[77]  Id. at 209.

[78]  Id.

[79]  Id. at 209–10.

[80]  W. Prosser, Handbook of the Law of Torts, 649 (4th ed. 1971).

[81]  Fleck v. KDI Sylvan Pools Inc., 981 F.2d 107 (3d Cir. 1992).

[82]  Id.

[83]  Id.

[84]  Richmond, supra note 57, at 210.

[85]  Id.

[86]  J. Timothy Eaton, Product Warnings in the Marketplace Are We Overdoing It?, Brief, Summer 1988, at 12, 32.

[87]  Restatement (Second) of Torts § 402A cmt. j (1965) (“Where warning is given, the seller may reasonably assume that it will be read and heeded; and a product bearing such a warning, which is safe for use if it is followed, is not in defective condition, nor is it unreasonably dangerous”).

[88]  Richmond, supra note 57, at 215. 

[89]  Traylor v. Husqvarna Motor, 988 F.2d 729, 735 (7th Cir. 1993).

[90]  Richmond, supra note 57, at 215.