Guaifenesin and Headaches: What Users Say

• cou...
• December 6, 2010

Guaifenesin for Bronchitis "Made coughing a lot easier after feeling like I was going to die from the phlegm that was blocking my air passage. I didn't give it a full 10 because it gave me a slight headache and a bit numb/tingling feeling all over my body but nothing to be alarmed about. Oh my goodness what a difference. I can breathe and finally sleep knowing I'm not going to choke to death. Thank you Mucinex."

• Sic...
• June 9, 2013

Guaifenesin for Cough "I had a runny nose, blocked ears, headache, and sore throat with mucus. It's great! I took one pill and saw relief, so 4 hours later I took the second one. Now I am wide awake. It's almost 4 am. Take it earlier."

• Bro...
• January 30, 2013

For Bronchitis "When I was using it in cough syrup without measuring it, I sometimes got a headache. However, taking the recommended maximum dose of 6 tablets per day (that is, every 4 hours), I have had no side effects except for a bit of mental fuzziness. It really helps me to expectorate thick mucus. A great side benefit is not having to endure that horrible taste that guaifenesin has! Very inexpensive (less than 15 cents per day) and very helpful for non-productive cough!"

• 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."

• Kwe...
• Taken for less than 1 month
• October 16, 2016

For Cough "Not long after taking my first dose of extra-strength Benylin for a persistent cold/respiratory infection, I became so dizzy I couldn't stand up and had to lie down. I closed my eyes and nodded off and woke up a while later feeling a little woozy but not dizzy. My head hurt the rest of the day. It did seem to help bring up phlegm that afternoon. I think I would take a half dose next time."

• 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."

• Cho...
• October 14, 2017

Guaifenesin for Bronchitis "I had tried this product in 2005, and it was not effective. So I gave it another chance to so-called redeem itself. Well, this is definitely not for me, it made me feel worse. I developed a headache."