In need of a good night’s sleep so you can wake up feeling refreshed? Look no further than ZzzQuil™ Sleep-Aid Products. But how does ZzzQuil work—and how should this medication be taken?
Although ZzzQuil is brought to you by the makers of Vicks® NyQuil®, it’s not for colds. It’s not for pain. It’s just for sleep.
ZzzQuil contains diphenhydramine HCI, which is a big word for a small compound that helps you sleep. To help you stay awake and alert, your body produces histamine, a naturally occurring substance that interacts with receptors in your brain to promote wakefulness. Diphenhydramine acts as an antihistamine, which blocks your brain’s alertness to make you feel the opposite: drowsy.
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Studies have shown that diphenhydramine relieves occasional sleeplessness when used as directed, by reducing the time it takes for you to fall asleep so you feel rested in the morning.
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The other great news about diphenhydramine? For more than 30 years, diphenhydramine has been approved by the FDA as an OTC (over-the-counter) medicine to treat occasional sleeplessness.
3 Plus, diphenhydramine is non-habit-forming.
ZzzQuil Liquid and
ZzzQuil LiquiCaps® Sleep-Aid Products contain diphenhydramine HCI so you can get a good night’s sleep—and wake up refreshed.
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1
Emanuel MB. Histamine and the antiallergic antihistamines: a history of their discoveries. Clinical and Experimental Allergy. 1999; 29:1–11.
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U.S. Code of Federal Regulation. 21 CFR 338—Nighttime sleep aid drug products for over-the-counter human use. 14 February 1989.
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