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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.

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Mucinex Vs. Benadryl: Which Works Best For Allergies?

Mucinex DM

(guaifenesin / dextromethorphan)

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Diphenhydramine

 

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Summary for Mucinex DM

Over-the-counter

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.

Indications for Mucinex DM

  • 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)

Pros and Cons for Mucinex DM

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

Common Side Effects for Mucinex DM

  • Side effects aren't common. See Other Side Effects.

Warnings for Mucinex DM

  • 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

Summary for Benadryl

Over-the-counter

Diphenhydramine, also known by the brand name Benadryl, is an over-the-counter antihistamine used to relieve allergy or common cold symptoms in adults and children. It comes as pills and a liquid and is typically taken by mouth every 4 to 6 hours as needed. Because it can make you drowsy, some people also use it as a sleep aid at bedtime. Common side effects include sleepiness, dizziness, and dry mouth.

Indications for Benadryl

  • Short-term relief of allergy or common cold symptoms (runny nose, sneezing, itchy nose or throat, and itchy or watery eyes) - people 6 years and older
  • Occasional trouble sleeping - people 12 years and older

Pros and Cons for Benadryl

Pros

  • Relieves allergy and cold symptoms in about 15 to 30 minutes
  • Safe for children as young as 6 years old
  • Available over the counter
  • Comes as pills and liquid

Cons

  • Can make you feel sleepy or dizzy
  • Might need to take multiple times a day for symptom relief
  • Not the best choice for older adults
  • Can worsen certain conditions like glaucoma and stomach ulcers

Common Side Effects for Benadryl

  • Sleepiness
  • Dizziness
  • Constipation
  • Blurry vision
  • Dry mouth

Warnings for Benadryl

  • Sleepiness
  • Accidental overdose
  • Worsening of certain health problems

Prices with our coupons for Mucinex DM vs. Benadryl

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Mucinex DM20 tablets / 600mg/30mg
$17.37$19.60
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Diphenhydramine30 capsules / 25mg
$9.49-
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