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Mucinex Fast-Max Severe Congestion & Cough and Diarrhea: What Users Say

Diarrhea: mentioned by 5 users (26.3%)

Based on user experiences from 19 Mucinex Fast-Max Severe Congestion & Cough reviews, the following table shows the most commonly mentioned side effects.

All user comments are moderated by Drugs.com. Each review is verified for relevance and screened for inappropriate content. Side effects are user-reported and not clinically verified.

diarrhea 26.3%
nausea 26.3%
anxiety 15.8%

Reviews for Mucinex Fast-Max Severe Congestion & Cough

Commonly mentioned side effects
  • Gir...
  • January 1, 2020

For Cough and Nasal Congestion "I’m only giving this a high rating because it did relieve my congestion and non-stop coughing. However, shortly after, I started having extreme anxiety, feeling like I was jumping out of my skin, and diarrhea. Maybe everyone doesn’t have the same side effects, that’s true, but this part was awful and would prevent me from taking it again."

6 / 10
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9 Report
  • Ty2...
  • February 1, 2018

For Cough and Nasal Congestion "I took the syrup version because I had been coughing up mucus in my lungs for about a week. Previously, I took Vicks NyQuil, but after using 24 oz, I thought that was a safer alternative. After 3 hours of taking a 15 mL dosage (the dosage cup was broken - had to use the NyQuil measuring cup, which says 15 mL and 30 mL), which is 5 mL less than the recommended dosage, I was getting a fever, had trouble urinating, vomited, and had diarrhea at the same time. I did the same thing last night, but I ended up just not getting any sleep from being nauseous. I wish I had read the warning on the product that said, 'do not take if your cough is phlegmy,' but you know how it is with medication, the retailers keep it so well packaged that you have to take it home and read the warnings after popping down $20 to purchase it. I am going back to NyQuil for $10 in the future, but will let this cough subside first."

1 / 10
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2 Report
  • LL9...
  • March 16, 2016

For Cough and Nasal Congestion "This medicine works great. I had mild diarrhea as a side effect, but my annoying mucus cough was relieved."

10 / 10
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6 Report
  • Smi...
  • Taken for less than 1 month
  • December 31, 2019

For Cough and Nasal Congestion "I usually take Alka-Seltzer Cold at work. Yesterday, I decided to try something different. Guess what, I'm up at 12:51 am with diarrhea. That's a bummer - never again."

8 / 10
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2 Report
  • Ann...
  • November 29, 2019

For Cough and Nasal Congestion "Worst product ever. Awful diarrhea, and I mean awful, hours lasting and painful. Instantly nauseous! Do not waste your money."

1 / 10
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4 Report

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Reviews may be edited to correct grammar/spelling or remove inappropriate content. Reviews appearing to come from parties with a vested interest are not published. This information is not intended to endorse any medication and should not replace the expertise and judgment of healthcare professionals.

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