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Compare Mucinex DM vs. Benadryl

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

Key takeaways

Mucinex DM (guaifenesin/dextromethorphan) and Benadryl (diphenhydramine) are both over-the-counter medications, but they serve different purposes. Mucinex DM is a combination of an expectorant and a cough suppressant, used to relieve coughs and loosen mucus in the chest. It comes in various forms like tablets, liquids, and granules, and is typically taken every 4 to 12 hours depending on the formulation. On the other hand, Benadryl is an antihistamine that treats allergy symptoms, common cold symptoms, and can also be used as a sleep aid. It is available in tablets, capsules, and liquid forms, and is usually taken every 4 to 6 hours for allergies or cold symptoms, and once at bedtime for sleep. While Mucinex DM can cause side effects like stomach upset and dizziness, Benadryl is known for causing drowsiness and dry mouth. Additionally, Benadryl should not be used long-term due to risks like memory problems, especially in older adults, whereas Mucinex DM is not meant for long-term use either but primarily due to its specific symptom relief focus.

drug combination

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  • Mucinex dm (guaifenesin / dextromethorphan)
    Diphenhydramine (Benadryl)
  • Mucinex dm (guaifenesin / dextromethorphan)
    Diphenhydramine (Benadryl)

  • Summary of Mucinex DM vs. Benadryl

    Summary for Expectorant / Antitussive

    Mucinex DM (guaifenesin / dextromethorphan) is an over-the-counter medication that's used to relieve cough and loosen mucus. It has two active ingredients: guaifenesin (an expectorant that clears chest congestion) and dextromethorphan (a cough suppressant that relieves cough). The medication is available as tablets, dissolvable granules, and liquid that are taken by mouth, each with different dosages, directions, and age limits. Extended-release tablets are taken every 12 hours, while the other forms are usually taken every 4 hours. Most people have few to no side effects when used as directed, but it can sometimes cause stomach upset, dizziness, and drowsiness.

    Summary for Antihistamine

    Diphenhydramine (Benadryl) is an over-the-counter (OTC) oral medication that's commonly used to treat allergies, common cold symptoms, and itching. Because it makes most people very sleepy, it can also be used as an occasional sleep aid.

  • Indications of Mucinex DM vs. Benadryl

    Indications for
    •Short-term relief of coughs caused by minor throat or lung irritation (e.g., common cold)
    •Loosens and breaks up mucus in the airways (chest congestion)
    Indications for
    •Allergies
    •Common cold symptoms
    •Trouble sleeping for people 12 years and older

  • Pros and Cons of Mucinex DM vs. Benadryl

    Pros and Const for Expectorant / Antitussive
    Pros
    •Available as a tablet, oral liquid, and dissolvable granules
    •Available over the counter without a prescription
    •Sugar-free options available, so okay to use for people with high blood sugar
    •Works within 30 minutes to help lessen cough
    Cons
    •Not meant to be used long-term
    •Might need to take multiple times a day to relieve symptoms
    •Many states require you to be over 18 to buy it because of risk of misuse
    •Can't cut or crush extended-release tablets
    Pros and Const for Antihistamine
    Pros
    •Can help relieve allergy and cold symptoms within about 30 minutes
    •Can be used in children as young as 6 years old with allergy and cold symptoms
    •Can help with occasional sleep problems (12 years and older)
    •Available as a lower-cost generic
    •Available OTC in several different dosage forms
    Cons
    •Not the best option for long-term use
    •Can cause drowsiness the next day when used for sleep
    •Can cause hyperactivity in some children
    •Might not be safe for people with breathing problems, glaucoma, or problems with urinating
    •Can impair your ability to drive or do tasks that require alertness

  • Common Side Effects of Mucinex DM vs. Benadryl

    Common Side Effects for
    •Side effects aren't common. See Other Side Effects.
    Common Side Effects for
    •Sleepiness
    •Dizziness
    •Dry mouth, nose, and throat
    •Headache
    •Constipation
    •Blurry vision

  • Warnings of Mucinex DM vs. Benadryl

    Common Side Effects for
    •Risk of overdose and misuse
    •Interactions with certain medications for Parkinson's disease and depression
    •Caution use in people with phenylketonuria (PKU) - dissolvable granules only
    Common Side Effects for
    •Accidental overdose
    •Excessive sleepiness
    •Worsening of certain health problems

  • Prices with our coupons for Mucinex DM vs. Benadryl

    Learn more about Mucinex dm
    Learn more about Diphenhydramine

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