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Guaifenesin / pseudoephedrine and Increased Heart Rate: What Users Say

Brand names: Mucinex D, Mucinex D Maximum Strength, Congestac, Decongest II, Ambifed-G, Guaifenex PSE 85, Deco-D, Mucus D, Coldmist Jr, ExeFen, Mucus Relief D, Entex PSE, Nalex CR, Mardrops-EX, Poly-Vent IR, Despec-Tab, Entex T, Guaimax-D, Anatuss LA, Fenex-PSE, G-Phed, Guaibid D, Guaifed, Nalex Jr, G-Phed- PD, Guaivent PD, Guaibid D Pediatric, Eudal SR, Duratuss GP (old formulation), Deconsal LA, D-Feda II, Guaifenex PSE 60, Demibid II, Guiadrine II, Guiatex II, Ambifed, Guiadrine II SR, Defen-LA, Desal II, GP 500, Guaifed-PSE, Guiadrine PSE 120, Guai-Vent/PSE, Guaifenex PSE 120, Guiatex PSE, Guai Sudo, Guaipax PSE, Ami-Tex PSE, Ru-Tuss DE, Guaifenex RX Guaitab Guiatuss PE Degen II Guaivent (Ethex) Tusnel Pediatric Drops Altarussin PE Sinutab Non Drying Robitussin Severe Congestion Humibid GC Guaifenex GP Dynex ExeFen-IR Durasal II Guiadrine PSE Guiatex II SR Coldmist Drituss GP Coldmist LA Guaifenex PSE 80 Aldex GS Despec-SR Maxifed Ambi 60/1000 Ambi 60/580 Ambi 80/780 Aquatab D Dose Pack …show all brand names

Increased heart rate: mentioned by 24 users (9.3%)

Based on user experiences from 257 Guaifenesin / pseudoephedrine 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.

insomnia 28.0%
anxiety 21.4%
increased heart rate 9.3%
tremors 5.8%
dizziness 5.4%
nausea 5.4%
drowsiness 5.1%
cough 3.9%
dry mouth 3.5%
tiredness 3.5%

Reviews for Guaifenesin / pseudoephedrine

Showing 24 reviews tagged with "increased heart rate". Clear filters to view all 257 reviews.
Commonly mentioned side effects
  • Bre...
  • Taken for less than 1 month
  • February 2, 2020

For Cough and Nasal Congestion "I have been laying here all night after taking Mucinex D. My brain won’t shut down. I am wide awake. Mucinex D does help with nasal congestion. I do not have the jitters or the racing heart. After reading the other reviews, I know now why I can’t sleep. UGH!"

7 / 10
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32 Report
  • Ple...
  • Taken for 2 to 5 years
  • July 3, 2019

For Cough and Nasal Congestion "I'm a 37-year-old male. I've taken Mucinex D at some point each winter for the last few years, typically to help with a lingering cough/mucus after a nasty head cold. Taken as directed, it works well for me, though I do get some of the racing heart/anxious feeling others have reported; it does not keep me awake at night. One surprising side effect is that every time I am on this medicine, I become like a porn star. I can make love to my wife for a solid 45 minutes to an hour before ejaculating. I don't know what particular ingredient in this medicine would cause that, but I've experienced it a handful of times."

10 / 10
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37 Report
  • Kma...
  • February 29, 2016

For Cough and Nasal Congestion "I took Mucinex D before bed because my sinuses were congested and I could feel mucus in my lungs, making it hard to breathe. Shortly after taking the medication, everything loosened up, my nose ran, but I could breathe. Unfortunately, it's now 6 AM, and I haven't slept a wink and have had a rapid heart rate and anxiety. I have a headache and am too jittery to sleep. I did feel slightly nauseous after I took the pill and very dry mouth now."

4 / 10
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30 Report
  • Anonymous
  • Taken for less than 1 month
  • October 22, 2015

For Cough and Nasal Congestion "I took this pill around 5:30 PM, and it's 11:17, and I'm usually asleep by this time. Keeps you up all night, makes you jittery, and it has you feeling like you're drunk. I hate the way I felt, and it worsened the way my sinus felt. Also, I've experienced heart racing, weird dreams, and blabbing off at the mouth. This product should be off the market."

1 / 10
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18 Report
  • Gol...
  • Taken for less than 1 month
  • December 20, 2015

For Cough and Nasal Congestion "Took Sudafed today and decided to try Mucinex D tonight for the congestion medicine in it. My sinuses are feeling less pressure, but it's 2:00 a.m., and I haven't slept a wink, and the way my heart is racing, I doubt I will. This should definitely be a daytime-only medication."

2 / 10
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18 Report

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  • AGa...
  • September 19, 2018

For Cough and Nasal Congestion "I took this medicine at 8 PM, hoping I would go to sleep normally and just feel better in the morning. Here I am at 1:36 AM, wide awake with 0 sleep and 0 sleepiness, which is super frustrating since I have a whole day of work starting at 8:30 AM. I didn't know the pseudoephedrine ingredient was so potent at keeping you awake, if I had known, I would have definitely not taken this. My heart is racing, and I just feel really anxious. I’m hoping this feeling will go away soon, as I’m getting worried."

2 / 10
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12 Report
  • Tha...
  • October 10, 2018

For Cough and Nasal Congestion "I took Mucinex D last night because of slight congestion. It’s currently 4 a.m., and I have the PSAT in 4 hours. I’m wide awake, with my heart pounding and ears rushing. Thought it was the worst case of test-taking anxiety I’ve had, but alas, it was the Mucinex (the pseudoephedrine part). I do NOT recommend this for night use."

2 / 10
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8 Report
  • Mik...
  • Taken for less than 1 month
  • June 30, 2017

For Cough and Nasal Congestion "Had congestion for 3 weeks. Doctor gave me antibiotics and suggested Mucinex D twice a day. The first two days seemed to help congestion somewhat, but I had no appetite and was somewhat anxious. The third night, I took it at 11 p.m. and slept about 2 hours. Woke up with my heart racing and anxiety. I couldn't sleep and was pacing. Effects started to wear off at 10 a.m. Wish I had seen this site first."

4 / 10
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8 Report
  • Anonymous
  • March 23, 2010

For Cough and Nasal Congestion "This medication cleared my completely congested nose in about an hour. I could breathe perfectly clearly through both nostrils! However, as others have mentioned, it made my heart race, and when I was exercising later that night, I felt lightheaded and had to quit early. I also couldn't sleep that night. My heart was feeling very fluttery, and I was wide awake in bed."

7 / 10
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14 Report
  • Nat...
  • February 19, 2018

For Cough and Nasal Congestion "No complaints, my husband left to go to the pharmacy at 2 AM to pick up anything to bring me comfort. I've had flu-like symptoms since last Wednesday, got through the worst but now left conquering thick phlegm that I'd have to cough so hard to try to get out, my head felt swollen and my eyes would get burning hot, bringing on horrible throat and headache. Ok, so took this at 2:15 AM, and within a half hour, I was asleep, and slept until I had to take my children to school at 8:30 AM. This has made the mucus so much easier to get 'up and out', I do not have to hack so hard. For my experience, this has helped so much, I wish I had taken this a full day earlier. He also got me the day/night pack, I plan on taking the night pill at about 7 PM, being that I hope I can make it to work tomorrow and want plenty of sleep. I feel sleepy now even with my 2:15 AM dose. I am normally very sensitive to medications but have not experienced high heart rate, dizziness, or nausea. I would buy again."

9 / 10
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5 Report
  • sle...
  • Taken for less than 1 month
  • September 23, 2019

For Cough and Nasal Congestion "I agree with so many that have left a review here! I do feel it helps with my cough and congestion, but I agree with the feeling of anxiety, heart racing, and most definitely sleepless nights (which is due to the pseudoephedrine in it)! I need my sleep. I may just take it in the AM or just not take it anymore. Not to mention it is very expensive for OTC (behind the pharmacy) medicine. My prescriptions with my insurance are way less than this!"

7 / 10
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6 Report
  • Anonymous
  • October 14, 2009

For Cough and Nasal Congestion "This worked on my sinuses, however, my heart rate increases so much that I feel jittery. The insomnia is a setback. The relief is great, but I'm not sure the things that go with it are worth it. Although my heart rate being up made me lose weight."

6 / 10
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13 Report
  • Can...
  • March 16, 2019

For Cough and Nasal Congestion "I took this for some relief of nasal and chest congestion. Let me warn you, do not take it, as within a half hour my heart was racing and I was jittery and anxious. On top of it, it made me sick to my stomach and I feel like someone is sitting on my chest. I can’t quench my thirst, no matter how much water I drink. I hope this feeling doesn’t last the entire 12 hours. This is horrible. I will never take this again, and this should be removed from the market."

1 / 10
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8 Report
  • Anonymous
  • February 25, 2011

For Cough and Nasal Congestion "When I took Mucinex D maximum strength for the first time, I did have great relief of congestion, but I also experienced a very scary rapid heartbeat, dizziness, and anxiety. The anxiety may be due to feeling like I had something really wrong going on, I'm not sure. I have taken many different OTC medications through the years and have never had an experience like this one."

2 / 10
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7 Report
  • Anonymous
  • May 17, 2011

For Cough and Nasal Congestion "This medicine is somewhat effective for me. I made the mistake of taking it before bed (I wish my doctor had warned me) and experienced a racing heart/was up most of the night. It did clear my sinuses, but not for 12 hours straight. I woke up at around 6 AM (having taken the medicine around 11 PM) with my nose entirely clogged again. I'm going to take Mucinex D again today, but not at night. I guess I'll just have to suffer tonight rather than be a complete insomniac."

7 / 10
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6 Report
  • So...
  • Taken for less than 1 month
  • December 30, 2017

For Cough and Nasal Congestion "I took one around 7:30 at night, and I’ve probably slept a few hours. I already have bad anxiety and a panic disorder, so this just pushed my anxiety through the roof. My nose feels so much better, but having this feeling is not worth it at all. I have the jitters, heart racing, and almost full panic attack. For others with this problem, I don’t recommend taking it at night and just be super cautious during the day. I’ll be staring at the wall for the next couple of hours, waiting for this to pass."

4 / 10
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3 Report
  • IAa...
  • February 2, 2018

For Cough and Nasal Congestion "I was starting to feel like a head and sinus condition was coming on, and with our tropical vacay coming up in 10 days, I for sure wanted to kick it in the butt. Well, I took my first dose this evening at 9 PM, went to bed because of an early work schedule, and slept soundly till 11:30 PM. It is now 2:30 AM, and I have experienced a rapid heartbeat, nausea, and jitteriness. I laid there for 2 hours thinking I could go back to sleep, and here I am. Kinda wished the pharmacist would have given me a heads-up. Now this is kickin' me in the butt!"

4 / 10
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5 Report
  • sim...
  • January 6, 2012

For Cough and Nasal Congestion "I have had major nasal congestion for over the past three weeks, and finally, after not being able to take it anymore, I found a local store to find some medicine. I spoke to the pharmacist who informed me about Mucinex D. I have been taking the two pills like clockwork over the last 3 days, with no relief. I have not experienced an increase in heart rate, nor have I experienced insomnia, but my nasal congestion is STILL here. Will have to schedule a doctor's visit for something that actually will work for me."

1 / 10
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4 Report
  • Anonymous
  • May 26, 2011

For Cough and Nasal Congestion "Allergies, pink eye = terrible congestion and a sore throat from all the eye drops. I took Mucinex D to ease the congestion a bit. It has thinned the mucus significantly; however, my stomach is very gassy and unsettled, and my heart is also racing! I haven't taken my temperature, but I feel a little feverish. Like many of you, I was not able to sleep last night. I will probably halve the dose tomorrow. But all in all, it's worth it. I can breathe, and that's probably the most important thing."

6 / 10
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3 Report
  • Ash...
  • Taken for less than 1 month
  • January 7, 2018

For Cough and Nasal Congestion "Took one pill at 8 PM. It’s now 3:32 AM, and my Apple Watch just calculated a 116 bpm heart rate. I’m also coughing so hard my rib is twinging. I think this drug is a hit or miss... my husband, who took it, is sound asleep next to me."

5 / 10
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0 Report
  • Kay...
  • Taken for less than 1 month
  • July 9, 2021

For Cough and Nasal Congestion "Had a sinus infection, so I took Mucinex D, one pill at 8 a.m. for two days, still had no relief, so on the third day I decided to take two pills. Later that night, I fell asleep at 10:30. Woke up 5 minutes later. Racing mind, racing heart. Couldn't fall asleep until 1 a.m. after drinking some tea. I thought I was going crazy. On the plus side, I have no more mucus in my sinuses."

5 / 10
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  • Anonymous
  • Taken for less than 1 month
  • January 28, 2018

For Cough and Nasal Congestion "This is my second day taking Mucinex for a bad cold. It’s not worth it! It has cleared my nose and throat completely, but I cannot get any sleep! Which is the pseudoephedrine side effect. I feel more miserable not being able to sleep than I did with the cold! On top of that, my heart has been racing for hours, and I started to get very anxious and nervous. I took this yesterday at 6 PM, it’s now 3 AM, and I’m wide awake. Never again!"

1 / 10
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2 Report
  • Jul...
  • January 22, 2018

For Cough and Nasal Congestion "I took it at about 5 PM today when my cough was getting worse. It is now 5:30 AM, and I haven't slept one bit. I am so jittery, nauseous, and dizzy. My heart is racing, and my whole body is shaking. My cough is significantly better, but the fact that I will not be getting sleep tonight for even a minute is quite the turn-off. I will never take this drug again."

1 / 10
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1 Report
  • Lil...
  • Taken for less than 1 month
  • November 19, 2020

For Cough and Nasal Congestion "Took two Mucinex D pills 12 hours apart for sore throat, post-nasal drip. After the second pill, my sore throat got worse, then I realized my tongue and throat had swelled up. Bad allergic reaction to this drug. I'll never take it again, it also made my heart race. Never again!"

1 / 10
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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.