Both medications areantihistaminesthat have sedative side effects.
Generic versions are also available.
These medications are meant to treat short-term sleep problems.
Emir Memedovski / Getty Images
If you experience occasionalinsomnia, you could use either Benadryl or Unisom to help you get to sleep faster.
you might also try alternative OTC sleep aids like melatonin or valerian.
Emir Memedovski / Getty Images
How Do Benadryl and Unisom Help With Sleep?
Diphenhydramine works by blocking natural substances called histamines.
This also has the effect of making you feel drowsy.
The sedative effect of diphenhydramine can last for up to seven hours.
Some of the sleep aids that have diphenhydramine as an active ingredient include:
Generic versions are also available.
Unisom’s active ingredient is the antihistaminedoxylamine succinate.
Doxylamine succinate is as effective as diphenhydramine but tends to work longer, for up to eight hours.
Popular sleep aids containing doxylamine succinate include:
It is also available in generic form.
Other Uses For Unisom and Benadryl
The active ingredients in Unisom and Benadryl are antihistamines.
These medications are also used to treat seasonal allergies.
Diphenhydramine is also the active ingredient in the OTC cold and flu remedy Benadryl.
Side Effects
Besides drowsiness, Benadryl and Unisom can both have unwanted side effects.
If they persist or are severe, stop taking the drug and let your healthcare provider know.
You should also call your healthcare provider if you have trouble urinating.
In older people, it is not recommended as it may cause excitation rather than sedation.
Call your healthcare provider immediately if you experience changes in vision or have trouble urinating.
It should never be given to children under 12.
Older people should not take it as it may cause excitation rather than sedation.
It should never be given to children 2 or younger.
When taken as directed, OTC sleep aids are unlikely to be addictive.
Older people should not take Benadryl or other products containing diphenhydramine.
Doing so can cause seizures, hallucinations, and a severe drop in blood pressure.
Do not take the night before a busy morning schedule.
Do note that the American Academy of Sleep Medicinedoes not recommendthese to treat insomnia.
Melatonin
Melatoninis a naturally occurring hormone that helps regulate thesleep-wake cycle.
This is the 24-hour pattern consisting of roughly 16 hours of daytime wakefulness and eight hours of nighttime sleep.
The regular release of melatonin from thepineal glandstimulates drowsiness and sleep.
The effectiveness of melatonin varies.
Some people claim that it works and leaves them feeling refreshed the next morning.
Others experience no benefits.
A 2019 review of studies found that melatonin can help improve sleep quality in people with secondary sleep disorders.
On the downside, the effect seems to decrease the longer you take melatonin.
As such, it should only be used for the short-term relief of insomnia when needed.
Melatonin is likely the safest OTC sleep aid.
Excess melatonin is quickly cleared from the body and does not accumulate.
Side effects are rare but may include headache, nausea, and vivid dreams.
Valerian Root
Valerian root(Valeriana officinalis) has been used for centuries to treat insomnia.
GABA is responsible for slowing nerve signals.
By activating these cells, valerian root may deliver a calming, sedative effect.
Despite its long-standing use in traditional cultures, the effectiveness of valerian root in treating insomnia is uncertain.
According to a 2015 report inSleep Medicine Reviews,valerian root had no discernible effect on insomnia.
There is no recommended dose for valerian root.
Although rare, liver damage can occur if valerian root is used excessively.
Doxylamine succinate tends to work longer and, unlike diphenhydramine, cannot be used in children under 12.
The effectiveness of natural sleep remedies like melatonin and valerian root is less certain.
Melatonin appears to work in some people but not in others.
The evidence supporting the use of valerian root for insomnia is generally weak.
If overused, valerian root can cause liver damage.
They are not recommended by the American Academy of Sleep Medicine.
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