Compare Benadryl vs. Sudafed

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

Benadryl
(Diphenhydramine)

Sudafed
(Pseudoephedrine)

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.Clears your sinuses. Sudafed (Pseudoephedrine) relieves stuffy nose, but it could keep you up at night. Don't forget your photo ID or you won't be able to buy it in the drugstore.
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Reviews & ratings
Button Group. All currently active
Button Group. All currently active
5.5767790262172285Benadryl
Reviews for Benadryl (Diphenhydramine)
85%
of people say Benadryl (Diphenhydramine) is worth it
57%
say it works well
8%
say it's a big hassle
Reviews for Sudafed (Pseudoephedrine)
82%
3% vs. Benadryl (Diphenhydramine)
45%
12% vs. Benadryl (Diphenhydramine)
6%
+2% vs. Benadryl (Diphenhydramine)
Side effects
BenadrylSudafed

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

FDA side effect reports for Benadryl »

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

FDA side effect reports for Sudafed »
How it works
BenadrylSudafed
Benadryl (Diphenhydramine) is an antihistamine. It blocks histamine, a chemical that causes congestion, itching, and other allergic reactions. It also makes you sleepy.Sudafed (Pseudoephedrine) is a decongestant. It narrows blood vessels and reduces swelling in your nasal passages to make breathing easier.
Type of medication
BenadrylSudafed
Antihistamine
1st generation
Prescription or OTC
DecongestantPrescription or OTC
Available as
BenadrylSudafed
  • Pill
  • Oral solution
  • Cream, gel, or ointment
  • Pill
  • Extended release
  • Liquid
Used for (click to learn more)
BenadrylSudafed
Risk factors for serious side effects
BenadrylSudafed
  • 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 »
  • History of high blood pressure
  • History of heart problems
  • Age 65 years or older
  • History of seizures
  • Women of childbearing age
Detailed Sudafed (Pseudoephedrine) risks & warnings »
Pregnancy category
BenadrylSudafed
BFDA pregnancy category (Probably safe)

Research studies with animals haven’t found a risk to unborn babies, but it hasn’t been properly studied in humans.

See the FDA package insert
NFDA pregnancy category (Unknown)

The FDA hasn’t classified this medicine’s effects on unborn babies. Talk with your doctor about this medicine if you’re pregnant or planning on it.

See the FDA package insert
Alcohol
  • Don't take it with alcohol or other drugs that make you sleepy.
No specific alcohol-related info.
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
  • 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.
  • It can affect the quality of your sleep, so you can't take it too close to going to bed.
Weight
No specific weight-related info.No specific weight-related info.
Upsides and benefits
BenadrylSudafed
  • 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.
  • One of the best over-the-counter options to clear stuffy nose and help you breathe better.
  • Clears nasal congestion better than other decongestants like phenylephrine.
  • Can be helpful in relieving congestion-related headaches and pressure in your ears.
  • Available in regular and extended release forms.
Downsides and risks
BenadrylSudafed
  • 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.
  • Pseudoephedrine (a decongestant) can make your heart race or make you feel anxious and restless.
  • It can affect the quality of your sleep, so you can't take it too close to going to bed.
  • Can raise blood pressure so check with your doctor before using it if you have high blood pressure or other heart conditions.
  • Sudafed (Pseudoephedrine) isn't as effective after using it for more than 4 days straight.
  • Need to show a photo ID to buy it in the drugstore and there is a limit on how much you can buy each visit.
Tips from our pharmacists for people taking the medication
BenadrylSudafed
  • 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.
  • 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.
  • If you only have itchy or watery eyes, try using just an antihistamine eye drop.
  • Starts working in 30 minutes.
  • You need to show an ID to buy Sudafed (Pseudoephedrine) in the drugstore because it contains pseudoephedrine.
  • Follow age-specific dosing instructions on how much to take. Don't take more than recommended on the package.
  • Don't take Sudafed (Pseudoephedrine) too close to bedtime since it can keep you awake.
  • Can cause an irregular or fast heartbeat, and can raise your blood pressure.
  • Talk to your doctor if your symptoms don't get better in 1 week.
Learn more
More about BenadrylSide effectsReviews & ratingsAlternativesFDA package insert
More about SudafedSide effectsReviews & ratingsAlternativesFDA package insert