What Is Diphenhydramine?
Diphenhydramine is an antihistamine.
Histamines are chemicals naturally produced by the body that enhance wakefulness.
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Diphenhydramine blocks h1 receptors, histamine pathways in the brain that are crucial for these wake-promoting effects.
In doing so, diphenhydramine can cause sleepiness.
This effect is beneficial for those who turn to over-the-counter sleeping pills to treat insomnia.
Diphenhydramine for Insomnia
The efficacy of diphenhydramine as a sleep aid is not well studied.
This is sometimes measured with a concept calledsleep efficiency.
Sleep efficiency is the total amount of sleep divided by the total amount of time spent in bed.
As reported by people who use the medication, it seems to improve.
In general, diphenhydramine is active for between four and six hours.
Nevertheless, morning side effects such as residual sleepiness or hangover can occur.
The older you are, the greater the risk of adverse effects.
Fall Risk
Diphenhydramine can cause decreased reaction times and dizziness.
The potential for bone fractures is a notable concern.
Cognitive Impairment and Dementia
Antihistamines like diphenhydramine can have anticholinergic effects as well.
This means that the medication acts on the signaling chemical called acetylcholine, which can have important consequences.
Growing evidence suggests chronic use of these medications may also be associated with the long-term development of dementia.
Drying Effects
There may also be drying effects.
It generally should not be used as a sleep aid in those ages 65 and older.
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