Robitussin and Birth Defects
Robitussin and Fertility FAQ

Yes, it's true. Robitussin might help you achieve pregnancy...

If you are using Robitussin or similar drugs and trying to achieve pregnancy, or have inadequate cervical mucus that hinders your  fertility, PLEASE READ THE LETTER BELOW which we received some years ago.  Note that the drug implicated, Dextromethorphan, is in some but not all cough syrups (ithas to be listed in the ingredients). So, instead of ignoring or advising against the use of guaifenesin, we offer this warning for those who may find it useful. 

The Couple to Couple League (CCL) has always stressed the limited use of PLAIN Robitussin (guaifenesin, generic), without other ingredients in those rare cases where it may improve cervical mucus enough to increase the probability of conception. You only need it when you're fertile, of course. Using it all cycle long will not increase your chances over using it just before ovulation. And if your mucus is normal, using it will have little effect. If you are using Clomid, you may experience some abnormally low mucus, and it may help. 

Other ingredients have no beneficial effect on fertility, and may be harmful, as the message below says. Some formulations add antihistamines which actually dry you up. So, please consult your doctor and NFP teachers before trying it. If you want to try it yourself, you can read the excellent FAQ below, from Fertility Plus. 


"Dear Cathy and Jim,

My Wife and her friend pulled your article, "A Primer on Natural Family Planning ," down from the internet.  It is a well-written document that gives a compelling case for Natural Family Planning.

However, on page 7 you recommend guaifenesin, an ingredient in Robitussin cough syrup, as a potential remedy for women who are having fertility problems because of overly short cervical fluid patches.  A recent study has shown that another ingredient in Robitussin, Dextromethorphan, causes severe birth defects in chicken embryos.  These include neural tube defects such as spinobifita and craniofacial anomalies including cleft lip and palate defects.  This was a study published in the January 1998 issue of Pediatric Research by a researcher named Rosenquist.  It was a follow up study based on earlier research correlating Robitussin use by pregnant women and severe birth defects in their children.

My wife works for the Cleft Palate foundation and the American Cleft Palate association.  Her name is Amy Mackin. You can reach her from 8:30 to 4:30 every day by calling (800)24CLEFT.  She tells me she got this information from the Association of Birth Defects in Children.  Their number is (800)313-2232. Amy operates a hotline for parents who have children with craniofacial anomalies. She has already had one caller who said she followed advice from the internet telling her to use Robitussin to increase her fertility. The woman gave birth to a child with a cleft. The woman then found the article correlating Robitussin use with clefts.

There is no way of showing that Robitussin caused the cleft palate on that woman's child or any other woman's child.  The relevant fact is that she now blames herself for causing her child's cleft.  I don't intend to be mean or harsh to you.  I found your article to be good, as I stated above. I only ask you to alter the document so that you recommend against using Robitussin to increase fertility, or possibly just don't mention Robitussin or other potentially harmful drugs for which you do not know the side effects in your report.  Also, please use your influence on the web to get the word out that a study has linked Robitussin to Birth defects.  This information is vitally important because families are following your advice in their attempts at becoming pregnant.


William A. Mackin
Graduate Student
UNC-CH Department of Biology"

Robitussin for Fertility FAQ

Using Robitussin/Guaifenesin to Improve Cervical Mucus

At first most people wonder what on earth a cough syrup has to do with fertility, but the logic is easily found in the fact that it is an expectorant and is being used to loosen and thin mucus - just in a different place than the lungs!

The name Robitussin was used in the title of this FAQ as it is a common brand of cough syrup in the United States. It is used on the fertility boards and newsgroups in the same manner as saying Band-Aid for an adhesive strip used to cover a cut. Any expectorant that contains guaifenesin as the only active ingredient is fine to use.

What kind of Robitussin is used to improve cervical mucus?

One should buy the plain kind with no letters after it. The only active ingredient is guaifenesin, and it contains 100 mg per teaspoon. It is very important to avoid the versions that contain decongestants as those may dry up cervical mucus.

Do I need to use the brand Robitussin?

No. Robitussin is the most common brand name, at least in the U.S., that carries a guaifenesin-only expectorant, but there are other brands and generics available. As long as the only active ingredient is guaifenesin, you can use any variety you find. For those with diabetes or otherwise concerned about sugar intake, there is the brand Diabetic Tussin available.

What is the recommended dose of guaifenesin?

The recommended dose for improving cervical mucus, based on a 1982 article in Fertility and Sterility, is two teaspoons (200 mg) taken orally three times per day. If mucus still appears thick and doesn't have good spinnbarkeit (ability to stretch), one can take as much as four teaspoons (400 mg) four times per day (the maximum dose on this over the counter medication). Each dose should be taken with a full glass of water, and attention should be given to drinking plenty of fluids throughout the day -- one needs water to produce mucus.

What cycle days should one take guaifenesin?

Just as the dose can vary a bit, so can the days. The article linked above had patients starting the guaifenesin on cycle day 5 - five days after the start of menses. This seems rather early as mucus is not an issue until about five days before ovulation - based on the fact that sperm can only live five days at best, and most pregnancies are the result of intercourse in the five days leading up to ovulation. Because of this information, it is now more common for doctors to suggest starting guaifenesin about five days before expected ovulation and continuing through ovulation day (six days total, for those with regular cycles). For those with irregular cycles, one should start taking guaifenesin about five days before the earliest day ovulation might be expected. For those taking Clomid (clomiphene citrate, Serophene) in a 5-day protocol, one can probably wait until the day after the last Clomid pill before starting the expectorant.

Is guaifenesin available in pill form?

Yes, but in most cases a prescription is needed. In the U.S., one can get a 600 mg time released caplet as the generic Guaifenesin CR, or brands Humibid LA, and Fenesin. This is often less expensive than the liquid.

How does one diagnose cervical factor/hostile mucus?

Many women try taking guaifenesin after noting little or no egg white (stretchy) cervical mucus while charting their fertility signals, but clinically it is diagnosed when a doctor checks mucus one or two days before ovulation in what is usually referred to as a post-coital test. The doctor does a vaginal exam and takes a sample of mucus to immediately analyze under a microscope to check for live sperm and for a ferning pattern. It is also checked for signs of infection. Quality mucus will be stretchy, fern, lack cellularity, and have live sperm swimming in it.

Why do so many women take guaifenesin while on Clomid?

Clomid (clomiphene citrate, Serophene) can cause hostile mucus in 30 percent or more of women using it. Higher doses tend to be more associated with less cervical fluid and a thinner uterine lining, than the 50 mg dose.

Will guaifenesin help if there is little or no mucus present?

Guaifenesin doesn't actually create mucus, it only thins what is already there. One would need to look into why there is no mucus (infection, not really ovulating).

Will taking guaifenesin cause any problems if it isn't needed?

Probably not. Since fertile mucus can be watery, there is probably no harm in taking guaifenesin and thinning it out.

What are some other possible ways to improve cervical mucus?

Drinking plenty of water should always be considered in addition to any other therapies one might try. Estrogen is sometimes given to help mucus production, though doctors have mixed opinions of its benefit, especially when used with Clomid (and some suggest using Tamoxifen instead of Clomid). Injectable gonadotropins used for controlled ovarian hyperstimulation often have a positive effect on cervical mucus as well. Some home/natural remedies include eating salty foods such as popcorn (mucus is very salty), taking evening primrose oil, avoiding dairy products (they can thicken mucus), eating lots of baby carrots, and also avoiding antihistamines, including high doses of vitamin C.

Does guaifenesin do anything for male factor infertility?

It is possible that men with thick semen may benefit from guaifenesin in the same manner it helps with cervical mucus in women. The suggested doses on the newsgroups and fertility boards range from two teaspoons twice per day to four teaspoons four times per day.

Copyright © 2000 by Rebecca Smith Waddell
All rights reserved. The text from this page be distributed as long as
full copyright, including URL, is attached and the use is not for profit.
Created: May 13, 2000

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