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Compare Promethazine vs. Nyquil

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

Key takeaways

Promethazine (Phenergan) and acetaminophen/dextromethorphan/doxylamine (Vicks Nyquil Cold and Flu) are both used to treat symptoms like runny nose and sneezing, but they belong to different medication classes. Promethazine is an antihistamine that also has anticholinergic and anti-dopaminergic properties and is used for allergies, nausea, and motion sickness. Nyquil Cold and Flu is a combination medication that includes an analgesic, a cough suppressant, and an antihistamine and is used for cold and flu symptoms. Promethazine is available by prescription in various forms, including tablets, syrup, and injection, while Nyquil Cold and Flu is available over-the-counter as a liquid or capsules. Promethazine can cause drowsiness and dizziness and should not be used in children under 2 years old. Nyquil Cold and Flu can also cause sleepiness and dizziness and should not be used with other medications containing acetaminophen. Both medications can interact with monoamine oxidase inhibitors (MAOIs) like selegiline (Zelapar) or phenelzine (Nardil).

  • Promethazine
    Nyquil cold and flu
  • Promethazine
    Nyquil cold and flu

  • Summary of Promethazine vs. Nyquil

    Summary for Antihistamine
    Prescription only

    Promethazine is a prescription medication with many uses, such as treatment or prevention of nausea, motion sickness, and allergy symptoms. Promethazine works by blocking several chemicals, including histamine, dopamine, and acetylcholine. It comes as tablets, an oral solution, rectal suppositories, and an injection. The dose of promethazine and how often you take it depends on your age and what medical condition you're taking it to treat. But it shouldn't be given to children younger than 2 years of age since it can cause serious breathing problems. Common side effects include sleepiness and dizziness.

    Summary for Analgesic / Cough suppressant / Antihistamine

    Nyquil Cold and Flu is a combination medication containing acetaminophen (a pain reliever), dextromethorphan (a cough suppressant), and doxylamine (an antihistamine). It's used to treat cold and flu symptoms, like sore throat, fever, cough, runny nose, sneezing, and aches, in adults and children. Nyquil Cold and Flu is available as pills and a liquid. This medication can make you feel sleepy and dizzy as side effects.

  • Indications of Promethazine vs. Nyquil

    Indications for
    •Runny nose, watery eyes, and other symptoms of allergies
    •Runny or stuffy nose that isn't caused by allergies
    •Rash, swelling, anaphylaxis, and other symptoms of an allergic reaction
    •Dermographism
    •Treatment or prevention of nausea and vomiting before and after surgery
    •Treatment or prevention of motion sickness
    •Treatment of pain along with other pain medications after surgery
    •Help to relax your body and produce a light sleep, particularly before a procedure
    Indications for

    Temporarily relieves common cold and flu symptoms, including:

    •Cough
    •Sore throat
    •Headache
    •Minor aches and pains
    •Fever
    •Runny nose
    •Sneezing

  • Pros and Cons of Promethazine vs. Nyquil

    Pros and Const for Antihistamine
    Pros
    •Available as a lower-cost generic
    •Available in different formulations, such as a tablet, syrup, and injection
    •Starts working within 20 minutes
    Cons
    •Can't be taken by children under 2 years old because risk of serious breathing problem
    •Higher risk of side effects in older adults
    •Can cause sleepiness
    Pros and Const for Analgesic / Cough suppressant / Antihistamine
    Pros
    •Available over the counter
    •Works within 30 minutes to relieve cold and flu symptoms
    •Available in capsules and a liquid
    •Combines three medications in one product for convenience
    •Available as a lower-cost generic
    Cons
    •Needs to be taken multiple times per day
    •Can cause extreme sleepiness
    •More difficult to customize the dose since it's a fixed combination of three medications
    •Need to avoid alcohol while taking it
    •Not meant for long-term use

  • Common Side Effects of Promethazine vs. Nyquil

    Common Side Effects for
    •Feeling drowsy or tired
    •Dizziness
    •Confusion
    •Dry mouth
    •Nervousness
    •Blurry vision

    The following side effects are those additionally reported with promethazine injection at the injection site:

    •Burning
    •Pain
    •Rash
    •Swelling
    Common Side Effects for
    •Sleepiness
    •Dizziness
    •Dry mouth

  • Warnings of Promethazine vs. Nyquil

    Common Side Effects for
    •Potentially life-threatening slow breathing (respiratory depression)
    •Serious tissue injury (Injection only)
    •Excessive sleepiness
    •Worsening of certain health problems
    •Seizures
    •Higher risk of infection (from low white blood cell count)
    •Risk of serious nerve problems (neuroleptic malignant syndrome)
    •Uncontrollable body movements
    Common Side Effects for
    •Liver damage
    •Serotonin syndrome
    •Accidental overdose
    •Worsening of medical conditions
    •Allergic skin reactions

  • Prices with our coupons for Promethazine vs. Nyquil

    Learn more about Promethazine
    Learn more about Nyquil cold and flu

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