P&G's brand extension ZzzQuil must face lawsuit alleging falsity of its "Non-Habit Forming" claim

Sneed v. Procter & Gamble Company, --- F.Supp.3d ----, 2025 WL 1017933, No. 23-cv-05443-JST (N.D. Cal. Apr. 4, 2025)

This case is about a product I recently noticed, “Nighttime Sleep Aid” products containing diphenhydramine hydrochloride as ZzzQuil. Sneed alleged that the “Non-Habit Forming” claim on the product was misleading, as diphenhydramine is in fact habit-forming/not different from other sleep aids.

The court rejected P&G’s preemption arguments, some of which were already rejected in an earlier opinion. Briefly, that opinion looked at a FDA tentative final monograph finding “little to no pharmacologic potential for abuse of the ingredients in OTC nighttime sleep-aids,” and that “antihistamines like diphenhydramine ‘have generally been regarded as having low abuse potential and no ability to create dependency.’” But the same monograph specifically concluded that “[t]he term ‘non-habit-forming’ is misleading, undesirable and probably false because it is very hard to prove that any product with psychotropic activity can be non-habit forming; but more importantly, there is an insinuation that other OTC sleep-aid products obviously are habit-forming.” Thus there was no preemption.

Here P&G also pointed to two FDA approval letters where the FDA approved for marketing two cough syrups containing diphenhydramine and their corresponding labels describing the products as “non-habit forming.” But those were cough medicines for temporary use, with less diphenhydramine present per dose, and a sleep aid would foreseeably be used more regularly than cough medicine. That label wasn’t “materially identical” to the one at bar. Nor did the FDA approval for “non-habit forming” cough-medicine labels showed that it must have “reversed its tentative view [on diphenhydramine being potentially habit forming] as it evaluated additional studies.” Fundamentally, the court wasn’t convinced that the claim here would challenge an approved label. There’s no federally approved label for ZzzQuil as to the challenged statements, and “circumstantial evidence surrounding the approval of a different drug with a different dosage—even if containing the same main ingredient—does not pose the risk of conflicting factual determinations about whether ZzzQuil specifically is habit forming.”

The court had previously found that Sneed failed to sufficiently allege that the product actually could be habit-forming; the amended complaint remedied that deficiency by adding citations to “a variety of scientific studies and articles,” including (1) a declaration that discussed clinical case reports; (2) a 2008 study where the researchers detected “a cocaine-like pattern of stimulation of [dopamine] transmission” in rats after the rats were provided with intravenous doses of diphenhydramine;1 (3) a 2002 study finding that individuals rapidly developed tolerance to the sedative effects of diphenhydramine when administered a 50 mg dose twice a day; and (4) a 2021 study reporting a 63% increase in intentional diphenhydramine exposures from 2005 to 2016, including a 230% rise in misuse among adults aged 55 and older.

P&G said that the sources (1) do not focus on diphenhydramine specifically, (2) are based on anecdotes, (3) involve the significant abuse of diphenhydramine rather than the use of the drug as directed, or (4) involve studies that expose test subjects to diphenhydramine at levels exceeding 50 mg per day. But none of that was enough to make the claim implausible given the evidence alleged. As another court wrote: “[t]he cited studies reference at least [the diphenhydramine] identified in the complaint and purport to document their [tendency for misuse and potential habit formation]. Discovery may expose that those studies contain vital flaws, but it is enough for now that the studies do not plainly refute the allegations in the complaint.”