Medically reviewed by Alan Lucks | MD, Alan Lucks MDPC Private Practice - New York on December 18th, 2025.
Guaifenesin is an expectorant used to relieve chest congestion by loosening mucus.
Dosage varies by age, form, and condition, with typical adult doses ranging from 200 mg to 400 mg every 4 hours.
Children's doses are lower and should be carefully measured according to age and weight.
Always follow package instructions or a healthcare provider’s advice, especially when combining with other medications.
Missed doses should be taken as soon as remembered, unless close to the next dose.
For personalized dosage guidance or telehealth consultations, Doctronic.ai offers expert AI-powered and doctor-assisted support 24/7.
Guaifenesin is a common over-the-counter medication used to relieve chest congestion by thinning and loosening mucus in the airways. This makes it easier to cough up and clear the mucus, helping you breathe more comfortably. Whether you’re dealing with a cold, bronchitis, or another respiratory condition, knowing the correct dosage of Guaifenesin is crucial for effective and safe treatment.
In addition to its primary use as an expectorant, Guaifenesin is often found in combination with other medications in over-the-counter cold and allergy remedies. These combinations can include antihistamines, decongestants, and pain relievers, which can address multiple symptoms simultaneously. However, it is crucial to read labels carefully to avoid unintentional overdosing of Guaifenesin or other active ingredients. Always consult with a healthcare professional if you are uncertain about the right combination of medications for your symptoms.
This guide breaks down how much Guaifenesin to take, when to take it, and what to watch out for, including a handy dosage chart for quick reference.
Form |
Strength |
Typical Adult Dose |
Typical Children’s Dose |
Frequency |
Route |
Maximum Daily Dose |
|---|---|---|---|---|---|---|
Tablet |
200 mg |
200-400 mg |
Not recommended under 4 years |
Every 4 hours |
Oral |
2400 mg/day |
Extended-release Tablet |
600 mg |
600 mg |
Not recommended under 12 years |
Every 12 hours |
Oral |
1200 mg/day |
Liquid Syrup |
100 mg/5 mL |
10-20 mL |
Depends on age (see below) |
Every 4 hours |
Oral |
2400 mg/day |
For adults and children over 12, Guaifenesin is typically taken every 4 hours, not exceeding 2400 mg per day. Extended-release tablets can be taken twice daily. The goal is consistent thinning of mucus to ease coughing and improve breathing.
Children under 12 should use Guaifenesin cautiously and only under the guidance of a healthcare provider. Dosage is usually based on weight and age, and liquid forms are preferred for easier dosing.
Adults usually take 200 to 400 mg of Guaifenesin every 4 hours as needed. Extended-release tablets are dosed at 600 mg every 12 hours. Do not exceed 2400 mg in 24 hours. It’s important to drink plenty of fluids to help the medication work effectively.
Children aged 4 to 6 years generally take 50 to 100 mg every 4 hours, not exceeding 600 mg per day. Those aged 6 to 12 years can take 100 to 200 mg every 4 hours, with a maximum daily dose of 1200 mg. Guaifenesin is not recommended for children under 4 years without medical advice.
If you forget to take a dose, take it as soon as you remember. If it’s almost time for your next dose, skip the missed dose-do not double up. Maintaining regular intervals helps keep the mucus thinned consistently.
Patients with liver or kidney impairment should consult a healthcare provider before using Guaifenesin. Dosage adjustments may be necessary to avoid accumulation and side effects.
While Guaifenesin is generally considered safe during pregnancy, it’s best to check with a healthcare provider. Breastfeeding mothers should also seek advice to ensure safety for the infant.
Taking more than the recommended dose can lead to nausea, vomiting, dizziness, or headache. In case of suspected overdose, seek emergency medical help immediately. Always store Guaifenesin out of reach of children and follow dosing instructions carefully.
Take with a full glass of water to help loosen mucus.
Do not crush or chew extended-release tablets.
Check other medications for Guaifenesin to avoid doubling up.
Consult a healthcare provider if symptoms persist beyond a week or worsen.
Use telehealth services like Doctronic.ai for personalized advice and quick access to doctors.
Understanding the right Guaifenesin dosage can sometimes be confusing, especially when managing other health conditions or medications. Doctronic.ai offers a unique AI-powered doctor experience that remembers your health history and provides tailored medical advice instantly. Whether you have questions about Guaifenesin or need a quick telehealth consultation, Doctronic’s 24/7 video visits connect you with licensed doctors across all 50 states for under $40.
With over 10 million users benefiting from Doctronic, it’s a trusted resource for modern, personalized primary care. Visit Doctronic.ai to get started and get answers that fit your unique health needs.
Guaifenesin is a helpful medication for clearing chest congestion, but proper dosing is key to safety and effectiveness. Follow dosage guidelines based on your age and condition, and don’t hesitate to seek personalized advice from healthcare professionals. If you want quick, reliable, and personalized support, Doctronic.ai makes it easier than ever to get expert guidance without leaving home.
Yes, but be cautious. Many combination cold medicines contain Guaifenesin. Check labels to avoid doubling the dose. When in doubt, consult a healthcare provider.
Guaifenesin is generally not recommended for children under four without medical supervision due to limited safety data.
Most people notice relief within 30 minutes to an hour after taking Guaifenesin, but it may take a few doses for the full effect.
Consult your healthcare provider before taking Guaifenesin during pregnancy to ensure it’s safe for your specific situation.
If symptoms persist or worsen after a week, seek medical advice. Telehealth services like Doctronic.ai can provide quick consultations to guide next steps.
Key TakeawaysGuaifenesin is an expectorant used to relieve chest congestion by loosening mucus.Dosage varies by age, form, and condition, with typical adult doses ranging [...]
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