★★☆Single study — solid evidence, such as one good trial or a large observational dataset, but not replicated at the top tier.
Unisom SleepTabs and SleepGels contain two different drugs
SleepTabs contain doxylamine succinate. SleepGels, SleepMelts and SleepMinis contain diphenhydramine. Only the ingredients panel says which is in the box.
What the study found
One sleep-aid brand sells two different drugs side by side
Unisom SleepTabs contain doxylamine succinate. Unisom SleepGels, SleepMelts and SleepMinis contain diphenhydramine. They sit under the same brand name on the same shelf, and the only way to tell which molecule is in the box is to read the ingredients panel.
The caveat · US labels read on one day in 2026
This was read off US label records on 6 September 2026, for one brand family. Brand compositions change, and a product carrying the same name in another country may contain something else again.