Guaifenesin and Nausea: What Users Say

• mel...
• February 23, 2014

Guaifenesin for Bronchitis "Took this medication for a chest cough before I went to bed. Woke up in the night with severe nausea and felt dizzy. Tried it again a week later and the same happened. I know other people who swear by it."

• ash...
• Taken for less than 1 month
• November 9, 2016

Guaifenesin for Bronchitis "This medicine doesn't work for me well... it made my nose more stuffy, dried my throat out, and kept me up... every time I tried to sleep, I would wake up coughing and feeling nauseous, and it seems to produce more mucus... drink lots of water!! Seriously...! But this will be my last time taking Mucinex, it's not for everybody, and it's definitely not for me."

• Nic...
• Taken for less than 1 month
• April 3, 2018

For Bronchitis "For everyone that suffers from allergies, I highly recommend this product: Mucinex DM 1200 mg guaifenesin. I'm using the 12-hour extended-release tablets, I've had allergies for over 10 years, and nothing really worked. I felt dizzy and nauseous at times, but then as my body adjusted to it, it cleared my ears of gunk. Whenever a headache comes on, drink water. I'm happy to share this because I've suffered a lot and was not enjoying quality of life. Please do try it. God bless."

• Jlo...
• Taken for less than 1 month
• May 15, 2020

For Cough "Omg! First of all, my stomach turned shortly after taking, and I had to run for the restroom! Then I was so nauseous and weak! This went on the entire day. I do not know what is in this stuff that made me worse than I started off, but I would never ever consider taking this again! Felt like a terrible flu!"

• Lit...
• Taken for less than 1 month
• April 17, 2019

Guaifenesin for Cough "I was hospitalized with a virus, and this was given to me. It was effective, but made me very sick and nauseous. When I got home, I saw that it contained menthol and wondered. Real Robitussin products do not make me feel sick, but this one did, and I won’t take it again. Too bad we are at the mercy of hospitals when we are sick and can’t make choices about products we take."

• sy9...
• Taken for less than 1 month
• January 2, 2016

Guaifenesin for Cough "I would give this a zero out of ten if it was possible. I rarely get sick, but I have been having a lot of trouble with a runny nose and coughing up mucus. This 'medicine' doesn't do anything. Not only does it taste terrible, but it's useless. Followed instructions, and I'm on day 7 with the same problems. Avoid this stuff."

• Cha...
• Taken for less than 1 month
• August 31, 2018

For Cough "I used guaifenesin for mucus relief with a cough. I drank a full bottle of water with it and 30 minutes later, ate supper. At 12:30, I woke up with vomiting and severe diarrhea. Blood pressure went sky high (from a normal low). Headache and dizziness. I couldn’t eat for 2 1/2 days because of the nausea. Blood pressure went back to normal after 24 hours. I have used other cold medicines, and every one would make me at least slightly nauseous. I didn’t know they all contained this ingredient. This seems to be abnormal for this medicine, so I think I may be allergic."

• Pup...
• Taken for less than 1 month
• May 16, 2016

Guaifenesin for Cough "I took this attempting to get rid of a cough and chest congestion. I am a 105 lb 30-year-old female. I took one pill yesterday and felt a little better. That was a half dose, so today I tried 2 pills, a full dose. After feeling nauseous for several hours, I finally threw up several times and am feeling much better. I will not be taking it again and would rather allow the congestion to run its course."

• Rya...
• October 28, 2019

For Cough "A doctor told me to take this med, guaifenesin, for my upper respiratory infection, and my goodness, did it make me sick. I'm nauseous, dizzy, and just really nervous ... I think I am going to go back to my doc and break his nose."

• Sky...
• December 29, 2022

Guaifenesin "When I first started using Mucinex, an oval-shaped pill, about seven years ago for cough congestion, they worked great. As the years progressed, whenever I had similar symptoms, Mucinex worked less and less. I switched to the liquid formula about three years ago with the same results. I am on day three of using Mucinex congestion and cough medicine. I will never take this medicine again because I feel a lot worse after starting it. I can't sleep because of excessive coughing that I didn't originally have, headache, which I rarely get, and nausea. Not worth it. I'll try home remedies the next time."

• Anonymous
• October 31, 2011

Guaifenesin for Cough "I took one tablet 12 hours ago and have been feeling very sick ever since. My nose is running, coughing, and feeling terrible, as if I had a bad cold. Not taking any more!"

• Anonymous
• April 11, 2011

Guaifenesin for Cough "This medicine made me sick. I took one 12-hour slow-release tablet with a large glass of water, and it's a week later, and I still feel nauseated."

• Jo7...
• January 15, 2017

Guaifenesin for Cough "Gave me diarrhea, dizziness, nausea, stomach cramps, and even some numbness in tongue/face. Worse than the cough. Never again."

• Tin...
• September 7, 2021

Guaifenesin "I took Mucinex Cold & Flu, and it works, but it made me have diarrhea, severe stomach problems, and nausea."

• mrs...
• Taken for less than 1 month
• May 4, 2022

Guaifenesin for Bronchitis "Took Mucinex once yesterday and was fine but a bit nauseous from it, even with food, today the second dose made me throw up and feel absolutely awful within an hour. Would not recommend."