Non-habit forming means no dependence, not that it keeps working
The front of a US sleep-aid pack reads Fall Asleep Fast and Non-Habit Forming. The warnings panel on the same box says to stop after two weeks of sleeplessness.
What the study found
The carton says non-habit forming and stop after two weeks
Both sentences are on the same box. The front of a US sleep-aid pack reads Fall Asleep Fast and Non-Habit Forming. The warnings panel says to stop and see a doctor if sleeplessness lasts more than two weeks. Non-habit forming is a claim about dependence, not about the drug still working.
The caveat · Permitted wording, not evidence
A label records what a regulator permits a company to print, not what the evidence shows. The dependence claim is narrowly defensible: diphenhydramine is not a controlled substance, and the one trial that looked found no rebound insomnia on stopping. This is one product from one manufacturer in one country.