What you need to know before buying Robitussin DM


Robitussin DM is an over-the-counter expectorant and expectorant. This medicine helps control coughs and runny discharge, making you more productive . It is widely available under the brand name Robitussin, and the same drug can be purchased at the store or in generic form .

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Common use

The ingredients in this medicine help thin mucus and suppress coughs. People generally take this medicine for coughs associated with colds, allergies, flu, and other respiratory conditions .

Robitussin DM and its generic analogues contain 10 mg of dextromethorphan HBr, a cough suppressant, and 100 mg of guaifenesin, an expectorant.

It cannot be used in children under 6 years of age without first consulting a pediatrician .


  • Adults 12 years and older: two teaspoons every four hours for coughing. Do not exceed six doses in 24 hours.
  • Children 6 to 12 years: One teaspoon every four hours. Do not exceed six doses in 24 hours.

Side effects

Each drug can cause side effects. Most are minor, and the benefits outweigh the risks.

  • Drowsiness or dizziness
  • Hives or skin rashes
  • Nausea, abdominal pain, or vomiting

Rare but serious side effects that you should report to your healthcare professional immediately:

  • Confusion
  • Excitement, nervousness, or anxiety
  • Severe nausea and vomiting
  • Speak slurred
  • Seizures or convulsions – in children
  • Cervical movements – in children
  • Slow or labored breathing – in children


Do not use this medicine if you are taking an MAOI (medicine for depression, mental, emotional or Parkinson's disease) or within two weeks of stopping the MAOI.

Consult your doctor before using this medicine if you have a chronic cough caused by asthma, smoking, or emphysema.

If you cough up a lot of mucus, taking cough suppressants can be problematic. Suppressing the cough can lead to secondary infections, such as pneumonia, because the mucus is in the lungs instead of being removed by coughing.

Talk to your doctor before taking this medicine if you are pregnant or breastfeeding.

Stop use and ask a doctor if:

  • Pain or cough that gets worse or lasts more than seven days.
  • The cough is accompanied by a fever, headache, or a rash that does not go away.

Do not give Robitussin or other cough suppressants to children younger than 6 years old.

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