DM Maximum

Dextromethorphan HBr, Guaifenesin · Solution · Oral

Over the counter Expectorant Sigma-1 Agonist Uncompetitive N-methyl-D-aspartate Receptor Antagonist

Active ingredient

Active ingredients (in each 20 mL) Dextromethorphan HBr 20 mg Guaifenesin 400 mg

Purpose

Purpose Cough suppressant Expectorant

Uses

Uses helps loosen phlegm (mucus) and thin bronchial secretions to rid the bronchial passageways of bothersome mucus and make coughs more productive temporarily relieves: cough due to minor throat and bronchial irritation as may occur with the common cold or inhaled irritants the intensity of coughing the impulse to cough to help you get to sleep

Warnings

Warnings Do not use if you are now taking a prescription monoamine oxidase inhibitor (MAOI) (certain drugs for depression, psychiatric, or emotional conditions, or Parkinson’s disease), or for 2 weeks after stopping the MAOI drug. If you do not know if your prescription drug contains an MAOI, ask a doctor or pharmacist before taking this product. Ask a doctor before use if you have persistent or chronic cough such as occurs with smoking, asthma, chronic bronchitis, or emphysema cough that occurs with too much phlegm (mucus) Stop use and ask a doctor if cough persists more than 1 week, tends to recur, or is accompanied by a fever, rash, or persistent headache. These could be signs of a serious condition. If pregnant or breast-feeding, ask a health professional before use. Keep out of reach of children. In case of overdose, get medical help or contact a Poison Control Center right away.

Do not use

Do not use if you are now taking a prescription monoamine oxidase inhibitor (MAOI) (certain drugs for depression, psychiatric, or emotional conditions, or Parkinson’s disease), or for 2 weeks after stopping the MAOI drug. If you do not know if your prescription drug contains an MAOI, ask a doctor or pharmacist before taking this product.

Ask a doctor before use

Ask a doctor before use if you have persistent or chronic cough such as occurs with smoking, asthma, chronic bronchitis, or emphysema cough that occurs with too much phlegm (mucus)

Stop use and ask a doctor

Stop use and ask a doctor if cough persists more than 1 week, tends to recur, or is accompanied by a fever, rash, or persistent headache. These could be signs of a serious condition.

Pregnancy or breast-feeding

If pregnant or breast-feeding, ask a health professional before use.

Keep out of reach of children

Keep out of reach of children. In case of overdose, get medical help or contact a Poison Control Center right away.

Directions

Directions do not take more than directed do not take more than 6 doses in any 24-hour period mL = milliliter only use the dose cup provided dose as follows or as directed by a doctor adults and children 12 years and over: 20 mL in dosing cup provided every 4 hours children under 12 years: do not use

Other information

Other information each 20 mL contains: sodium 6 mg store at 25°C (77°F); excursions permitted between 15°-30°C (59°-86°F) use by expiration date on package

Inactive ingredients

Inactive ingredients anhydrous citric acid, FD&C red #40, flavors, glycerin, propylene glycol, purified water, sodium benzoate, sodium citrate dihydrate, sorbitol solution, sucralose, xanthan gum

Questions?

Questions or comments? 1-800-426-9391

Label text from the FDA structured product label by CVS WOONSOCKET PRESCRIPTION CENTER, INCORPORATED (revised Jul 27, 2026). Long sections are shortened; the complete label is on DailyMed.

Active ingredients

Dextromethorphan Hydrobromide in 1 product
Guaifenesin in 1 product

DM Maximum NDC products (1)

NDC	Strength & form	Labeler	Type
51316-310	Dextromethorphan Hydrobromide 20 mg/20mL; Guaifenesin 400 mg/20mL Solution	CVS WOONSOCKET PRESCRIPTION CENTER, INCORPORATED	OTC MONOGRAPH DRUG

Frequently asked questions

What is DM Maximum used for?

Who makes DM Maximum?

DM Maximum is listed by 1 labeler in the FDA NDC directory, including CVS WOONSOCKET PRESCRIPTION CENTER, INCORPORATED.