How Are Cough Suppressants Different From Expectorants?

Two Medicines for Coughing With Two Very Different Functions

Doctor listening to patient's cough
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Cough suppressants (also known as antitussives) are supposed to help control coughing by decreasing the urge to cough. Expectorants actually make you cough more. They promote more mucus production to make coughing more effective at removing bacteria. Learn what medication is best, depending on your type of cough.

Productive vs. Dry Coughs

Whether you need a cough suppressant or an expectorant depends on the type of cough you have. Coughs that produce mucus or phlegm are helping your body's immune system fight infection and should be encouraged with an expectorant. 

An expectorant's increased mucus production is said to help get rid of the bad stuff in your lungs, but the extra dripping and irritation might not be worth it and could even lead to increased inflammation that encourages more dry coughing.

Dry coughs that do nothing but keep you awake at night don't benefit from—or react to—an expectorant. For those coughs, you can try a cough suppressant. However, there isn't any evidence that clearly shows that suppressants help at all.

Suppressants May Not Be Effective

There are lots of cough suppressants on the market, though studies have shown mixed results with their efficacy. Honey works a little, but the urge to cough is such a complicated process that researchers are still trying to find a medicine that will truly suppress coughs.

Some coughs are caused by mucus draining from the nose into the back of the throat. An expectorant encourages the production of mucus and improves the effectiveness of the cough, but the extra drainage might be lead to more coughing while laying down. If sleep is important—and most doctors encourage plenty of rest when you're fighting an infection—then taking something that makes it harder to sleep might not be the best option.

Using an Antihistamine Plus Decongestant

Coughs due to mucus might be reduced by the use of an antihistamine with a decongestant. They don't do anything about your cough per se, but they stop the mucus from dripping back there and tickling your throat—which should give you some relief.

The problem with antihistamines and decongestants is that they can cause anxiety. Since nasal drip is a nighttime problem, taking the drugs to help you sleep could backfire—the dripping may stop but anxious thoughts may keep you awake.

When to See Your Doctor

For really irritating coughs or coughs that last more than three days, your doctor may be able to prescribe a stronger cough suppressant. More importantly, seeing the doctor for a persistent cough could identify the underlying cause, which is the only real way to fix a cough.

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