Mucinex contains the active ingredient guaifenesin, which is thought to thin cervical mucus and help women get pregnant, although there is no clinical data to support this theory.
Women taking a common over-the-counter cold medicine are being warned that it could cause an unexpected pregnancy.
Doctors say there is anecdotal evidence that taking Mucinex makes it easier for sperm to travel through the vagina and reach the egg.
Social media and forums are filled with women claiming to have conceived while taking the $1 pill after years of struggling with fertility.
The theory is that because the drug works by thinning phlegm, it may also produce mucus in the cervix, creating an easier route for sperm to reach the egg.
However, doctors warn that Mucinex can cause vomiting, dizziness and headaches in rare cases at high doses.
A woman in a viral TikTok video claimed she had been “trying to conceive for years” and “doing anything” to get pregnant, but was unsuccessful until she took a decongestant medication containing guaifenesin, the active ingredient in Mucinex.
User @cassiemadams posted a video saying, ‘I’ve been trying to conceive for years only to take Mucinex and get pregnant. (I don’t know) what kind of magic is in those pills but here we are.’
But while Cassie was happy to be pregnant, there were many users who commented that they would “never take Mucinex again” in case it caused an unwanted pregnancy.
A reproductive expert told DailyMail.com there was no solid evidence that Mucinex or guaifenesin increased the chances of conceiving, but there was plenty of indirect evidence.
Dr. Karen Tang, a gynecologic surgeon from Pennsylvania, published a… video explaining the theory behind guaifenesin and increasing fertility, saying that the ingredient is meant to loosen the mucus people have when they are sick, making it easier to cough up.
This has led people to wonder whether the ingredient could make cervical mucus thinner, allowing sperm to travel more easily to reach a woman’s egg, fertilize it and result in a pregnancy.
Dr Rachel McConnell, from the Columbia University Fertility Centre, told DailyMail.com that cervical mucus around the time of ovulation, when a woman is most fertile, becomes thinner and “slippery”, helping sperm to travel.
Because guaifenesin thins mucus in the respiratory tract, the theory is that women who have thick cervical mucus may find that guaifenesin thins that mucus as well.
Dr. McConnell added, “Mucinex may be helpful for women who have thick cervical mucus as the sole cause of their infertility. However, patients should consult with their fertility physician to determine if Mucinex may be beneficial for them.”
TikTok user @cassiemadams said in a video that she and her partner had been trying “everything and everything” to get pregnant but were unsuccessful until she took guaifenesin.
The idea that guaifenesin can increase the chances of pregnancy has been around for a long time, but the only study The study that was carried out on it was done in 1982.
Researchers looked at 40 couples who were having trouble conceiving after 10 months. Researchers took cervical mucus samples from the women before and after taking guaifenesin.
Twenty-three couples saw an improvement in the “quality” of their cervical mucus, and 15 of them were able to conceive. However, Dr Tang noted that there was no control group in the study to compare the guaifenesin-treated group with.
With 2 million views, hundreds of people have commented on Cassie. videosharing similar stories.
User Ahzbah commented: “I haven’t been given protection for 5 years. They both got really sick one week and took Mucinex. They now have a happy 7 month old baby.”
Another, SunshineRnbwSkttlz23, said: ‘I have PCOS and tried multiple fertility treatments over the years… tried Mucinex once and BOOM! 7 months pregnant.’
And while some welcomed the news, others said their pregnancies were unplanned because of the medication.
TikTok user Marcia Hofer commented: “My baby Mucinex turned 1 in December but we didn’t try it. She just had a cold.”
Ellie Bagwell claimed she became pregnant while taking Mucinex even though she was on birth control.
While another added: “I got sick and now have a one year old. They should definitely put that on the warning label!”
One commenter described herself as “a Mucinex victim,” while another said she got pregnant “but tried NOT TO GET PREGNANT.”
And others gave up taking the medication for fear that they too might become pregnant unexpectedly.
One person commented that she was currently sick and was taking Mucinex: “Don’t scare me like that.”
Mariska Alexus said: ‘Wow, that’s my go-to medication too… goodbye Mucinex forever.’
In a TikTok video, Cassie said she took the generic version of Mucinex purchased at Target that contained the same active ingredient, guaifenesin.
And Kalico Mermaid expressed her fear: “Enough, I’m between two prescriptions (for birth control) and I’ve been taking Mucinex because I’ve been sick too. They’re scaring me.”
In a separate video, Cassie said she took the generic version of Mucinex purchased at Target.
While not the brand name Mucinex, the brand name version contains the same active ingredient, guaifenesin.
He said he took one pill every 12 hours of the extended-release version.
In a third video, Cassie explained that she took the medication for five days, starting a few days after her menstrual cycle ended.
She added that she and her partner were “doing everything they could” to conceive.
Cassie said: “I think it worked. We just changed a few things in the latest version.”
While Cassie did not detail any side effects she may have experienced, common side effects of guaifenesin include headache, rash, nausea and vomiting, diarrhea, and difficulty sleeping.
More recently, there was a case in 2010 study A 32-year-old man was being evaluated for infertility. His doctor prescribed guaifenesin. Two months later, a semen analysis showed significant improvement in sperm count and motility.
The authors wrote: “The evidence for the efficacy of guaifenesin is almost entirely anecdotal. Given the mechanism of action of guaifenesin, it is unclear in this case why the patient demonstrated such a large improvement in both sperm count and motility.”
They called for further investigation into the matter.
Reckitt, the maker of Mucinex, told Good Morning America: ‘Reckitt is aware of the recent social media activity around Mucinex and fertility, and we understand why there is increased interest in this topic.
‘As a global leader in health and hygiene, it is important to clarify that Mucinex should only be used as directed on the label. Taking Mucinex for infertility constitutes off-label use.
‘Taking any medication outside of the approved indications or without knowing all the active ingredients can be harmful. If in doubt, we recommend that women consult their doctor.
‘Always read the label and safety information before taking any personal care medication.’