Guaifenesin is an expectorant available in over-the-counter (OTC) medicines that make coughs more productive by loosening chest congestion and ridding the airways of bothersome mucus. Guaifenesin can be the only active ingredient in a cough medicine, or it can be found in multi-symptom cough and cold products. Guaifenesin may also be found in medicines that treat bronchial asthma.
Common Products
- Little Remedies®
- Primatene® Tablets
- Triaminic®
- Store Brands (ex. Walmart’s “Equate” store brand or CVS Health store brand)
Dosing Information
Different types of products containing this active ingredient have different strengths. That’s why it is always important to read and follow the Drug Facts label. Most medicines warn against use of an active ingredient for longer than 7-10 days. Stop use and ask a doctor if symptoms persist.
A Note to Families:
1. Scientific and medical authorities around the world recognize acetaminophen as the only analgesic considered safe for use throughout an entire pregnancy when used according to the Drug Facts label.
2. There are no studies showing that acetaminophen use in children or during pregnancy causes autism.
3. Autism has many known risk factors, including genetics, but there is no clear, single cause.
4. Major health authorities like the FDA, CDC, and healthcare organizations such as the American College of Obstetricians and Gynecologists (ACOG) do not have warnings against acetaminophen use during pregnancy based on any known risk of autism and all recommend acetaminophen as the safest analgesic to use during pregnancy for short-term pain relief.
Frequently Asked Questions:
In fact, the Autism Science Foundation (ASF), a non-profit organization funding scientific autism research, specifically states that: it is disingenuous and misleading to boil autism's causes down to one simple thing," as there are hundreds of genes linked to autism in addition to other complex environmental factors.
Additionally, the most recent and rigorous research on this topic does not show a causal link to autism. The 2024 study published in the Journal of the American Medical Association (JAMA) analyzed nearly 2.5 million children using the gold-standard sibling comparison method, which controls for shared genetics and family environment, and found no association between acetaminophen use during pregnancy or infancy and neurodevelopmental issues such as autism.
- CDC Yellow Book (Current as of April 23, 2025): “Acetaminophen remains the non-opioid analgesic of choice during pregnancy.”
- FDA’s Acetaminophen Page (Current as of August 14, 2025): “To date, FDA has not found clear evidence that appropriate use of acetaminophen during pregnancy causes adverse pregnancy, birth, neurobehavioral, or developmental outcomes.”
Additionally, the Society for Maternal-Fetal Health, a professional organization for obstetricians with subspecialty training in maternal-fetal medicine, stated on September 25, 2025 that it: "...continues to advise physicians and patients that acetaminophen is an appropriate medication to treat pain and fever during pregnancy…the weight of scientific evidence that acetaminophen use during pregnancy causes an increased risk for autism or ADHD is simply inconclusive…”
Safety Guide
Safety Guide
Guaifenesin is approved by the U.S. Food and Drug Administration (FDA) and is safe and effective when used according to the Drug Facts label directions.
Ask a healthcare provider before use if:
- If you are allergic to guaifenesin or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems.
- You have breathing problems (such as emphysema, chronic bronchitis, asthma, smoker's cough) or large amounts of mucus.
Do not use if:
- Do not give an OTC cough medicine or multi-symptom cough and cold medicine containing guaifenesin to a child under the age of 4.
Stop use and ask a doctor if:
- Your cough lasts for more than seven days, returns, or occurs with a fever, rash, or persistent headache. These additional symptoms could be signs of a more serious illness.
- You take too much. Immediately contact a healthcare provider or the poison control national helpline at 800.222.1222.
What are the side effects of guaifenesin?
- Nausea or vomiting may occur.
- A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.