An expectorant is a medicine you can use when you have a cough that produces mucus. Expectorants help thin the secretions in your airway and loosen up mucus, so you can make your cough more productive. Expectorants are generally safe to use, but it’s important to read labels and speak with your healthcare provider about any possible interactions.

What is an expectorant?

An expectorant is a type of cough medicine used to help clear mucus (phlegm) from your airway. You may take an expectorant to help relieve congestion if you have a cold or the flu. Expectorants are available as standalone drugs or as an ingredient in an all-in-one cold or flu medication.


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What does an expectorant do?

Expectorants are used to treat the symptoms of respiratory tract infections. These types of infections include the common cold, bronchitis and pneumonia. These infections can cause a buildup of mucus in your throat and lungs. You may develop a cough and your chest may hurt due to mucus accumulation. Expectorants help relieve these symptoms.

Expectorants are used to make coughing up mucus easier. They don’t stop the cough as cough suppressants do. At times, you want a productive cough — you don’t want to subdue (suppress) it. This is because coughing is your body’s way of clearing your airway of bacteria and other germs.

How do expectorants work?

Expectorants lubricate your airway. This helps loosen up the mucus and make the secretions in your airway thinner. By loosening up the mucus, expectorants make your cough more productive. This makes it easier for you to cough up mucus effectively and clear your throat.

Coughing up the mucus can help with the discomfort you may feel from chest congestion. In addition, since the mucus may contain infectious debris such as bacteria and viruses, coughing it up lowers your risk of infection.


What are the different types of expectorants?

Expectorants can be classified as medicinal or natural. The main ingredient in medicinal expectorants helps thin the secretions in your airway. By thinning those secretions, it makes your cough more productive. Medicinal expectorants are available over-the-counter in liquid, pill and tablet forms. Medicinal expectorants include:

  • Guaifenesin: Guaifenesin is the most commonly used expectorant. It is the active ingredient in medicines including Mucinex® and Robitussin®. You can find guaifenesin in many common cough, cold and flu medications. In addition, guaifenesin is an active ingredient in over-the-counter decongestants, cough suppressants, antihistamines and pain and fever medications. Guaifenesin is currently the only expectorant approved by the U.S. Food and Drug Administration. Guaifenesin hydrates your mucus in order to reduce its stickiness.
  • Potassium iodide: Potassium iodide is a prescription-strength expectorant. Your healthcare provider may prescribe potassium iodide if you have a chronic lung disease. Chronic lung diseases can produce excessive mucus, which can complicate your disease. These diseases include asthma, bronchitis and pulmonary emphysema. Potassium iodide helps loosen mucus and makes it easier to cough.

Natural expectorants are another option if you’re trying to loosen up mucus and relieve chest congestion. Natural expectorants include:

  • Menthol: Menthol is a natural chemical that comes from plants in the mint family. Menthol is a common ingredient in cough drops (throat lozenges) and cough syrups. Menthol gives you a cooling sensation and can sometimes soothe a sore throat. One study determined that menthol may relax your airway muscles. This allows more air to enter your respiratory system to help improve your cough.
  • Ivy leaf extract: Ivy leaf extract is a natural expectorant known for its effects on mucus production. One study said that any medications containing dry ivy extract may be effective at treating coughs.
  • Oral hydration: No matter what kind of expectorant you use, keeping hydrated is important. Drink extra water or make a cup of tea to increase your fluid intake. Avoid alcohol and caffeine as much as you can.
  • Steam: Inhaling warm, moist air can do wonders for a persistent cough. The steam can help loosen the mucus in your airway. Take a long shower or use a humidifier to get extra moisture into your lungs.
  • Honey: Honey may help loosen up mucus and relieve your cough. You can add honey to a cup of tea or even mix it with warm milk. But don’t give honey to babies younger than 12 months old — they have an increased risk of botulism.

Do I need to worry about any interactions with expectorants?

If you’re taking other medications, it’s important to speak with your healthcare provider or pharmacist before taking an expectorant. Expectorants can alter the effects of certain other medications you take. You may have an increased risk of serious side effects as well.

In addition, since expectorants are sometimes combined with other medications, you need to carefully read labels. Certain combination cold and flu medications contain ingredients that may be harmful to you. For instance, some combination medications contain phenylephrine. Phenylephrine can cause high blood pressure and a slow heart rate (bradycardia). Also, phenylephrine may interact with antidepressants and heart medications.


What are the side effects of expectorants?

Expectorants usually don’t cause serious side effects. But the different types of expectorants do have various potential side effects.

Guaifenesin is typically safe to use if taken as directed. Potential side effects of guaifenesin can include:

  • Dizziness.
  • Constipation.
  • Headache.
  • Tiredness (fatigue).
  • Rash.
  • Nausea and vomiting (if taken in high doses).

Side effects with potassium iodide are more likely and possibly more severe. The side effects of potassium iodide can include:

  • Abdominal pain.
  • Nausea and vomiting.
  • Acid reflux.
  • Diarrhea.
  • Skin rash.
  • Numbness in hands or feet.
  • Swelling or tenderness in your salivary glands.
  • Excess salivation.
  • Sore gums.
  • Brassy, metallic taste in your mouth.
  • Confusion.
  • Headache.
  • Tiredness (fatigue).
  • Irregular heartbeat (arrhythmia).

Menthol is usually safe unless you’re allergic to it. If you’re having an allergic reaction to menthol, the possible side effects can include:

  • Hives.
  • Difficulty breathing.
  • Wheezing.
  • Swelling of your face or throat.

The possible side effects of ivy leaf extract can include:

  • Nausea and vomiting.
  • Diarrhea.
  • Hives.
  • Skin rash.

Expectorants combined with other medications, such as all-in-one cold or flu medication, are more likely to cause side effects. These side effects can include:

A note from Cleveland Clinic

Having a cough is no fun. But sometimes it’s important to clear out extra mucus and the bacteria and particles that come with it. That’s where expectorants come in. Taking an expectorant will help thin and clear your airway, creating a more productive cough. In no time, the cough should be gone and you’ll be feeling better. Be sure to speak with your healthcare provider if your cough lingers or you have other concerns. And always read the labels of expectorants for possible interactions or side effects.

Medically Reviewed

Last reviewed on 11/19/2021.

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