Compare Phenylephrine vs. Dayquil Cold And Flu

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

Sudafed Pe
(phenylephrine)

Dayquil Cold And Flu
(acetaminophen / phenylephrine / dextromethorphan)

Clears your sinuses. Sudafed Pe (Phenylephrine) is a good medication for relieving stuffy nose. It doesn't work as well as pseudoephedrine (Sudafed), but it has fewer side effects.Relieves cold and flu symptoms. Dayquil Cold And Flu (Acetaminophen / Phenylephrine / Dextromethorphan) is a useful combination medicine that relieves cold and flu symptoms, but make sure you really need all of its ingredients.
Reviews & ratings
Filter group. All currently selected
Filter group. All currently selected
4.18Phenylephrine
Reviews for Phenylephrine
44%
of people (All ages) say Phenylephrine is worth it
24%
say it works well
10%
say it's a big hassle
164 reviews
Have you used Sudafed Pe (phenylephrine)?
Worth itNot sureNot worth it
Reviews for Dayquil Cold And Flu
81%
-37% worse vs. Phenylephrine
38%
-14% worse vs. Phenylephrine
5%
-5% worse vs. Phenylephrine
1034 reviews
Have you used Dayquil Cold And Flu (acetaminophen / phenylephrine / dextromethorphan)?
Worth itNot sureNot worth it
Side effects
PhenylephrineDayquil Cold And Flu

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

FDA side effect reports for Phenylephrine »

We haven’t found good data for Dayquil Cold And Flu side effects.

FDA side effect reports for Dayquil Cold And Flu »
How it works
PhenylephrineDayquil Cold And Flu
Sudafed Pe (Phenylephrine) is a decongestant. It narrows blood vessels and reduces swelling in your nasal passages to make breathing easier.Dayquil Cold And Flu (Acetaminophen / Phenylephrine / Dextromethorphan) is a combination medicine that treats cold and flu symptoms. Acetaminophen relieves pain and reduces fever. Dextromethorphan is a cough suppressant. Phenylephrine is a decongestant that clears your sinuses.
Type of medication
PhenylephrineDayquil Cold And Flu
Prescription or OTCOver-the-counter
Available as
PhenylephrineDayquil Cold And Flu
  • Pill
  • Nasal spray
  • Eye drops
  • Suppository
  • Pill
  • Liquid
Used for
PhenylephrineDayquil Cold And Flu
Risk factors for serious side effects
PhenylephrineDayquil Cold And Flu
  • History of high blood pressure
  • Taking MAO inhibitors
  • History of heart problems
  • Age 65 years or older
  • Women of childbearing age
Detailed Sudafed Pe (phenylephrine) risks & warnings »
  • Drinking more than 2 alcoholic beverages a day
  • Taking with other Tylenol-containing medicines
  • History of liver disease
  • History of high blood pressure
  • Taking MAO inhibitors
Detailed Dayquil Cold And Flu (acetaminophen / phenylephrine / dextromethorphan) risks & warnings »
Pregnancy

Research studies with animals found harmful effects on unborn babies. It hasn’t been properly studied in humans. The benefits might outweigh the risks even if you’re pregnant. Talk with your doctor.

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.

Kidneys and liver
PhenylephrineDayquil Cold And Flu
No kidneys and liver related info.
  • To avoid hurting your liver, you have to keep track of the total amount of acetaminophen (APAP) you're taking since it's a very common ingredient in pain and cold/flu combination medicines.
Pain
PhenylephrineDayquil Cold And Flu
No pain related info.
  • The pain reliever (acetaminophen) is easier on your stomach and has fewer drug interactions than other pain medications like aspirin or ibuprofen.
Upsides and benefits
PhenylephrineDayquil Cold And Flu
  • Works to clear nasal congestion and helps you breathe better.
  • Helpful in relieving congestion-related headaches.
  • Has fewer side effects than other decongestants like pseudoephedrine.
  • It doesn't raise your blood pressure and heart rate as much, or cause as much trouble falling asleep.
  • Doesn't give you rebound congestion (worse symptoms when you stop taking it) like nasal spray decongestants do.
  • Dayquil Cold And Flu (Acetaminophen / Phenylephrine / Dextromethorphan) is a combination medicine that relieves multiple cold symptoms. It's good to use if you have a stuffy nose, a cough, fever, and pain.
  • The decongestant (phenylephrine) has fewer side effects than other decongestants like pseudoephedrine. It doesn't raise your blood pressure and heart rate as much, or cause as much trouble falling asleep.
  • The pain reliever (acetaminophen) is easier on your stomach and has fewer drug interactions than other pain medications like aspirin or ibuprofen.
Downsides and risks
PhenylephrineDayquil Cold And Flu
  • Phenylephrine doesn't last as long as other decongestants like pseudoephedrine (Sudafed).
  • You shouldn't use it if you have high blood pressure.
  • Can make your heart race or make you feel anxious and restless.
  • Shouldn't use it before you want to sleep.
  • Not as effective after using it for 4 days in a row.
  • If you don't really need all of the medications in this combination, you're taking extra medicine and might have extra side effects for no reason.
  • Phenylephrine doesn't last as long as other oral decongestants like pseudoephedrine.
  • You shouldn't use it if you have high blood pressure.
  • To avoid hurting your liver, you have to keep track of the total amount of acetaminophen (APAP) you're taking since it's a very common ingredient in pain and cold/flu combination medicines.
Tips from our pharmacists for people taking the medication
PhenylephrineDayquil Cold And Flu
  • Starts working in 30 minutes.
  • Phenylephrine can make you restless, so don't take it too close to bedtime.
  • It's in other cold and flu combination medicines. Read labels closely so you don't accidentally double up and take too much of it in a day.
  • Follow age-specific dosing instructions on how much to take.
  • Let your doctor know if your symptoms don't improve in a few days.
  • Phenylephrine, the decongestant, can make you restless, so don't take it too close to bedtime.
  • If you get the liquid form, use the dosing cup to measure the exact amount of medicine you need.
  • Follow age-specific dosing instructions on how much to take.
  • Contains acetaminophen, also known as Tylenol or APAP. Taking too much can cause liver failure and death. Don't take more than what's recommended on the package or with other Tylenol-containing products.
  • Let your doctor know if your symptoms don't improve in a few days, or if you have a really bad sore throat with a fever, headache, nausea, or vomiting.
Learn more
More about PhenylephrineSide effectsReviews & ratingsAlternativesFDA package insert
Have you used Sudafed Pe (phenylephrine)?
Worth itNot sureNot worth it
More about Dayquil Cold And FluSide effectsReviews & ratingsAlternativesFDA package insert
Have you used Dayquil Cold And Flu (acetaminophen / phenylephrine / dextromethorphan)?
Worth itNot sureNot worth it