Compare Unisom vs. Benadryl

Head-to-head comparisons of medication uses, side effects, ratings, and more.

Unisom Sleeptabs
(Doxylamine)

Benadryl
(Diphenhydramine)

Treats allergy symptoms and helps you sleep. Unisom Sleeptabs (Doxylamine) can help you get a good night's sleep, but you can have a hard time waking up if you don't give yourself enough time to sleep.Treats allergy symptoms and helps you sleep. Benadryl (Diphenhydramine) is great for allergies, but curl up on the couch after taking it and get ready for a nap.
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Reviews & ratings
Button Group. All currently active
Button Group. All currently active
4.428076256499134Unisom
Reviews for Unisom Sleeptabs (Doxylamine)
58%
of people say Unisom Sleeptabs (Doxylamine) is worth it
32%
say it works well
11%
say it's a big hassle
Reviews for Benadryl (Diphenhydramine)
85%
+27% vs. Unisom Sleeptabs (Doxylamine)
57%
+25% vs. Unisom Sleeptabs (Doxylamine)
8%
+3% vs. Unisom Sleeptabs (Doxylamine)
Side effects
UnisomBenadryl

We haven’t found good data for Unisom side effects.

FDA side effect reports for Unisom »

We haven’t found good data for Benadryl side effects.

FDA side effect reports for Benadryl »
How it works
UnisomBenadryl
Unisom Sleeptabs (Doxylamine) is an antihistamine. It blocks histamine, a chemical that causes congestion, itching, and other allergic reactions. It also makes you sleepy.Benadryl (Diphenhydramine) is an antihistamine. It blocks histamine, a chemical that causes congestion, itching, and other allergic reactions. It also makes you sleepy.
Type of medication
UnisomBenadryl
Antihistamine
Ethanolamine derivative
Prescription or OTC
Antihistamine
1st generation
Prescription or OTC
Available as
UnisomBenadryl
  • Pill
  • Chewable tablet
  • Liquid
  • Pill
  • Oral solution
  • Cream, gel, or ointment
Used for (click to learn more)
UnisomBenadryl
Risk factors for serious side effects
UnisomBenadryl
  • Using other drugs with similar ingredients
  • Age 65 years or older
  • Taking with alcohol
  • Taking other medicines that make you less alert
  • Children age 6 years or younger
  • Enlarged prostate
  • History of bladder problems
  • Glaucoma
  • Nursing mothers
Detailed Unisom Sleeptabs (Doxylamine) risks & warnings »
  • Using other drugs with the same ingredients
  • Age 65 years or older
  • Taking with alcohol
  • Taking other medicines that make you less alert
  • Children age 6 years and younger
  • Enlarged prostate
  • History of bladder problems
  • Glaucoma
  • Nursing mothers
Detailed Benadryl (Diphenhydramine) risks & warnings »
Pregnancy category
UnisomBenadryl
Alcohol
  • Drinking alcohol while taking Unisom Sleeptabs (Doxylamine) isn't recommended.
  • Don't take it with alcohol or other drugs that make you sleepy.
  • Don't take it with alcohol or other drugs that make you sleepy.
Food
No specific food-related info.No specific food-related info.
Kidneys and liver
No specific kidneys and liver-related info.No specific kidneys and liver-related info.
Sex
No specific sex-related info.No specific sex-related info.
Sleep
  • Shouldn't be used unless you have a full night to sleep.
  • Has fewer side effects than prescription sleep aid medications.
  • Not habit-forming like other sleep aids can be.
  • Unisom Sleeptabs (Doxylamine) makes you tired, so take it before you go to sleep.
  • Unisom comes in two different generic forms, doxylamine (Unisom SleepTabs) and diphenhydramine (other Unisom products). Both are antihistamines that help you sleep.
  • People age 65 years and older have a higher risk of side effects from taking antihistamine medications like Unisom Sleeptabs (Doxylamine). Watch for changes in vision, severe dry mouth, trouble urinating, or constipation. The drowsiness caused by Unisom Sleeptabs (Doxylamine) can make you "unsteady" on your feet, leading to a higher chance of falls.
  • Benadryl (Diphenhydramine) makes you tired, so take it before you go to sleep.
  • People age 65 years and older have a higher risk of side effects from taking antihistamine medications like Benadryl (Diphenhydramine). Watch for changes in vision, severe dry mouth, trouble urinating, or constipation. The drowsiness caused by Benadryl (Diphenhydramine) can make you "unsteady" on your feet, leading to a higher chance of falls.
Weight
No specific weight-related info.No specific weight-related info.
Upsides and benefits
UnisomBenadryl
  • Works well to help you fall asleep and doesn't make you feel groggy the next morning.
  • Has fewer side effects than prescription sleep aid medications.
  • Available over the counter without a prescription.
  • Not habit-forming like other sleep aids can be.
  • Benadryl (Diphenhydramine) is often better than other antihistamines at treating allergy symptoms and hives.
  • It can provide quick relief of allergy symptoms for both kids and adults.
  • It makes you sleepy, so it'll help if your allergies are bothering you at night.
  • The effects wear off in 4 to 6 hours, so side effects don't last that long.
  • It comes as a tablet, capsule, liquid, and quick dissolving tablet.
Downsides and risks
UnisomBenadryl
  • Shouldn't be used unless you have a full night to sleep.
  • You shouldn't drive after taking Unisom Sleeptabs (Doxylamine) until you know how it affects you.
  • Drinking alcohol while taking Unisom Sleeptabs (Doxylamine) isn't recommended.
  • It can increase the risk of falls, so elderly people shouldn't use Unisom Sleeptabs (Doxylamine).
  • Benadryl (Diphenhydramine) makes you more tired than Claritin, Allegra, or Zyrtec.
  • You shouldn't drive after taking Benadryl (Diphenhydramine) until you know how it affects you.
  • Talk to a pediatrician before giving Benadryl (Diphenhydramine) to a child.
  • It can increase the risk of falls, so elderly people shouldn't use Benadryl (Diphenhydramine).
  • Don't use Benadryl (Diphenhydramine) if you are breastfeeding.
Tips from our pharmacists for people taking the medication
UnisomBenadryl
  • Starts working in 30 minutes.
  • Unisom Sleeptabs (Doxylamine) makes you tired, so take it before you go to sleep.
  • Unisom comes in two different generic forms, doxylamine (Unisom SleepTabs) and diphenhydramine (other Unisom products). Both are antihistamines that help you sleep.
  • Don't take it with alcohol or other drugs that make you sleepy.
  • If you need to use it for more than a few weeks, talk with your doctor. A different medication might work better for you long-term.
  • Take it as needed every 4 to 6 hours.
  • Benadryl (Diphenhydramine) can make you dehydrated, so avoid this side effect by drinking plenty of fluids.
  • Benadryl (Diphenhydramine) makes you tired, so take it before you go to sleep.
  • If you only have itchy or watery eyes, try using just an antihistamine eye drop.
  • Don't take it with alcohol or other drugs that make you sleepy.
  • If you need to use it for more than a few weeks, talk with your doctor. A different medication might work better for you long-term.
Learn more
More about UnisomSide effectsReviews & ratingsAlternativesFDA package insert
More about BenadrylSide effectsReviews & ratingsAlternativesFDA package insert