As more states legalize marijuana for recreational use, the long-term effects of marijuana use —the good and the bad — will continue to have a significant effect on the law, and in particular, products liability law. Products liability actions generally come in three strains: (1) manufacturing defects; (2) design defects; and (3) failures to warn. A growing issue for those in the chain of distribution will be the contents of a product’s label and whether it provides for an adequate warning of the side effects associated with consumption. After all, the law on products liability has always held that “[p]roviding an inadequate warning is no better than providing no warning at all.”¹

This potential for liability has been exacerbated by the recent uptick of a long-known but oft-forgotten illness associated with heavy and prolonged marijuana consumption: Cannabinoid Hyperemesis Syndrome (CHS). In fact, a recent study conducted at two Colorado hospitals showed that since 2009, when medical marijuana became widely available, emergency visits for CHS nearly doubled. Symptoms of CHS include nausea, vomiting, abdominal pain, dehydration, and kidney failure. Despite the dire symptoms associated with CHS, the symptoms subside within days of ceasing marijuana consumption. Nonetheless, CHS goes against the grain of the commonly held belief that marijuana is a relatively safe substance; more Americans than ever before believe that marijuana consumption is harmless.

This commonly held belief may prove to be an Achilles heel for marijuana growers, distributors, and retailers in terms of the failure to warn. Making matters worse, the discovery of the side effects associated with marijuana consumption is in its infancy because the legalization of recreational marijuana is such a recent phenomenon. Nevertheless, the duty to stay informed of any side effects discovered by the scientific community and to ultimately pass such information on to the consumers so as to assure they are aware of these side effects will fall on marijuana growers, distributors, and retailers.

Some states with legalized recreational marijuana have attempted to address these issues through labeling requirements. For example, Washington requires labels affixed to marijuana products include the following warnings, among other information: (1) “This product has intoxicating effects and may be habit forming”; (2) “Smoking is hazardous to your health”; (3) “There may be health risks associated with consumption of this product”; and (4) “Should not be used by women that are pregnant or breast feeding[.]”²

It is unclear whether these requirements will be enough to inoculate marijuana growers, distributors, and retailers from liability under a failure to warn theory. Courts have imposed liability when faced with a product that fails to warn of known or reasonably scientifically knowable risks.³ Adequacy of a warning is a question of fact, which is determined on a case-by-case basis. But a product must warn of specifically known illnesses and diseases that may arise in connection with the use of the product in a foreseeable manner.⁴ Excessive and prolonged use of a product may be foreseeable and require warning. Most courts have carved out an exception to liability based on inadequate warnings when the risk associated with the manner in which the product is used is generally known and recognized.⁵ Yet, the perception among a majority of Americans is that marijuana consumption is harmless. Thus, it is unclear whether this exception will provide an avenue for escaping liability.

Marijuana growers, distributors, and retailers seeking refuge behind the regulations espoused by their states may find their efforts ineffective. Courts have held that, while evidence of a product’s compliance with appropriate regulations is relevant, such evidence does not necessarily defeat a products liability action.⁶ For example, in the context of FDA regulations, many courts have treated such regulations as setting minimum requirements, the compliance with which does not dispose of the duty to warn of possible side effects or dangers when there is actual or constructive knowledge.⁷ Consequently, any notion of comfort that may be found by complying with a state’s marijuana labeling requirements must be balanced with skepticism.

The recent uptick in CHS occurrences should put marijuana growers, distributors, and retailers on notice that the landscape of liability in connection with the sale of recreational marijuana is ever-evolving. These effects, in turn, will have enormous repercussions on the liability faced by marijuana growers, distributors, and retailers for the warnings they affix to their products. All parties involved in the chain of distribution should not be satisfied with merely complying with their state’s labeling requirements. The rise of CHS is just the latest serious side effect discovered with marijuana consumption; however, it poses the first opportunity for marijuana growers, distributors, and retailers to go above what their state’s labeling regulations require and nip potential liability in the bud.