Guaifenesin (Mucinex) Dosage Guide for Adults and Kids - GoodRx (2024)

Guaifenesin is a common over-the-counter (OTC) cough medication that goes by many brand names. Some examples include Mucinex and Q-Tussin. It’s also available as a generic medication.

Guaifenesin is an expectorant. This means it helps make it easier to cough up mucus and clear up chest congestion. Guaifenesin is often included with other medications in combination cold products.

With guaifenesin in many OTC cold medicines, it’s important to know how much is safe to take. Let’s review the typical adult and children’s guaifenesin dosages. Keep in mind, we’ll be focusing on the dosages for products that only contain guaifenesin — not combination products.

What guaifenesin dosage forms are available?

Guaifenesin comes in many different dosage forms. The amount of guaifenesin per dose varies depending on the product.

Always read the instructions on the label carefully before taking guaifenesin. Use the provided dosing cup if you’re taking guaifenesin oral liquid. Or ask your pharmacist for a dosing device to measure the liquid.

As mentioned above, many combination cold products have guaifenesin in them. Ask a healthcare professional before taking more than one cold medicine. It’s easy to accidentally take too much guaifenesin by taking multiple products.

What’s the typical guaifenesin dosage for adults?

Guaifenesin is made by many different manufacturers, and the dose may vary between products. When deciding on an OTC guaifenesin product, review the label to see how much guaifenesin is in each dose. Be sure to include guaifenesin from all sources.

Guaifenesin ER tablets, such as Mucinex maximum strength

Guaifenesin ER is the only standalone guaifenesin product sold under the brand name Mucinex. There are two different guaifenesin ER tablets available. And the recommended guaifenesin ER dosage depends on which version you’re taking.

Mucinex regular strength dosage (600 mg tablets): Take 1 to 2 tablets (600 to 1,200 mg) by mouth with a full glass of water every 12 hours as needed. Don’t take more than 4 tablets (2,400 mg) in 24 hours.

Mucinex maximum strength dosage (1,200 mg tablets): Take 1 tablet (1,200 mg) by mouth every 12 hours with a full glass of water as needed. Don’t take more than 2 tablets (2,400 mg) in 24 hours.

Good to know: Guaifenesin ER tablets release medication slowly over 12 hours. You shouldn’t cut, chew, or crush the tablets. Doing so can cause the tablet to release the medication too quickly, potentially causing more side effects. Your dose may also wear off sooner.

Guaifenesin IR tablets

Like the ER tablets, there are two versions of guaifenesin IR tablets: 200 mg and 400 mg tablets. And the dosage depends on which one you’re taking.

Guaifenesin IR 200 mg dosage: Take 1 to 2 tablets (200 to 400 mg) by mouth every 4 hours. Don’t take more than 12 tablets (2,400 mg) in 24 hours.

Guaifenesin IR 400 mg dosage: Take 1 tablet (400 mg) by mouth with a full glass of water every 4 hours. Don’t take more than 6 tablets (2,400 mg) in 24 hours.

Guaifenesin oral liquid

The adult guaifenesin liquid dosage is 10 to 20 mL (200 to 400 mg) by mouth every 4 hours. Don’t take more than 6 doses (up to 2,400 mg) in 24 hours.

What’s the typical children’s Mucinex dosage?

There are no brand-name Mucinex products labeled as “children’s Mucinex” that only contain guaifenesin. Brand-name Children’s Mucinex products contain guaifenesin and at least one other active ingredient. But there are generic guaifenesin-only products that have children’s dosage instructions on them.

Certain forms of guaifenesin can be safely given to children as young as 2 years old. Children ages 12 years and older can follow the adult guaifenesin dosage instructions for all the products discussed above. Don’t give children under 12 years old guaifenesin ER or IR tablets. Ask a healthcare professional for help if you don’t see a dose for your child’s age listed on the package instructions.

Guaifenesin oral liquid

Guaifenesin oral liquid can be given to children ages 2 years and older. Children’s guaifenesin liquid dosages depend on your child’s age. Below, we’ve provided a handy table to help you find the right dosage. But always ask a healthcare professional if you’re unsure how much to give your child.

Can adults take children's Mucinex?

Yes, adults can take children's Mucinex. Children’s guaifenesin products typically include a dosage for people ages 12 and older, as listed in the table above. You’ll want to look for that age range on the directions section of the OTC label. This could be worded as “ages 12 years and older” or “adults and children 12 years and older.”

If you’re unsure about how much to take, ask your pharmacist.

Are there any dosage adjustments for medical conditions?

In general, there are no special guaifenesin dosage adjustments for people with kidney or liver problems. But there are people who should speak with a healthcare professional before taking it.

These include people who:

• Have a chronic cough caused by smoking, asthma, or chronic obstructive pulmonary disease (COPD)

• Are pregnant

• Are allergic to artificial sweeteners

• Have severe kidney disease

• Have diabetes

The above health conditions don’t always mean you can’t take any guaifenesin products. But you may need to avoid certain formulations, or your healthcare team may want to follow up with you while taking it.

What happens if you miss a dose of guaifenesin?

Guaifenesin is an as needed medication. This means that you only take it when you have symptoms. But it’s important to wait the required amount of time between doses. Make sure there’s at least 4 hours between guaifenesin IR tablets and oral solution. And wait at least 12 hours between doses of guaifenesin ER tablets.

What happens if you take too much Mucinex?

Taking too much Mucinex can cause excess side effects like upset stomach, dizziness, and headaches. So taking an extra dose by mistake is unlikely to harm you.

Mucinex overdoses are typically only seen when people are taking combination Mucinex products, such as Mucinex DM (guaifenesin / dextromethorphan). And the potential overdose symptoms, such as hallucinations and trouble breathing, are likely due to the dextromethorphan component of these products — not the guaifenesin.

Still, you should only take the recommended dosages of guaifenesin. If you suspect that you or someone you know has taken too much guaifenesin and you’re concerned, contact a healthcare professional or call Poison Control at 1-800-222-1222.

How to save on guaifenesin

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