You've heard people swear by the benefits of humidifiers when they feel sick, but do they actually help when you have a cough and feel under the weather? Ultimately, whether using a humidifier for a cough is good or bad depends on what's behind your cough — and the type of humidifier you use.
Humidifier for Dry Cough
"Humidifiers work better for some coughs than others," says Janet Morgan, MD, an internal medicine and geriatrics specialist at the Cleveland Clinic's Beachwood, Ohio, location. "If your cough is caused by irritation from dry air or congestion from an upper respiratory infection, a humidifier may add moisture to relieve a cough or to break up mucus in your lungs."
The Cleveland Clinic notes that dry air can wreak havoc on your respiratory health, and a humidifier can help relieve your symptoms and be a sound preventative measure. Per the Cleveland Clinic, if the air in your house is so dry that your hair stands on end or you get a touch-spark, it could cause a dry cough.
Per the U.S. Environmental Protection Agency, you want your indoor relative humidity (RH) to be between 30 to 50 percent, ideally. The Mayo Clinic says the best way to check the RH is with a hygrometer, a thermometer-like device that can keep a read on the air's moisture level. Mayo Clinic recommends that if you do buy a humidifier, you should purchase one with a built-in hygrometer, called a humidistat.
Humidifier for Acute vs. Chronic Cough
A humidifier is also good for an acute cough, Dr. Morgan says. An acute cough, according to the National Heart, Lung, and Blood Institute, is one that lasts less than three weeks and is typically caused by cold viruses, sinusitis or pneumonia.
If your cough is one that persists for a longer period of time, say, a chronic cough from an underlying issue, check with your doctor. "If you have a cough from a long-term lung disease like asthma, COPD or allergy, you should ask your doctor about using a humidifier first," Dr. Morgan says.
When Not to Use a Humidifier
As the American Academy of Allergy Asthma & Immunology (AAAAI) explains, if you have indoor allergies, a humidifier can do more harm than good, as common causes of indoor allergy like dust mites and mold spores thrive in moist air.
Cleveland Clinic adds that high moisture can encourage bacteria, mold, mildew and dust mites — as well as trigger allergies and asthma.
Moreover, per AAAAI, standing water inside a humidifier leaves mineral deposits that increase the growth of bacteria and can lead to an allergic attack or sinusitis. If you have allergies, AAAAI suggests that you check with your doctor before using a humidifier for cough.
Per Mayo Clinic, humidifiers come in both cool mist or steam varieties (the latter is also known as a vaporizer). Regarding which is ideal for an acute cough caused by a cold, Mayo Clinic notes that cool-mist humidifiers may help, whereas heated humidifiers may not. But, Mayo Clinic adds, more research is needed to confirm.
Otherwise, Mayo Clinic notes that each type is equally effective at adding moisture to the air.
"If your humidifier is not properly cleaned and maintained," Dr. Morgan says, "it can spread mold, bacteria or minerals into the air. In that case, a humidifier is not good for anyone. Even if you don't have allergies, a poorly maintained humidifier can make you sick."
Central home humidifiers are built in, so you don't have to clean them yourself, Mayo Clinic says, but free-standing cool-mist or steam vaporizers, while mobile, do require maintenance.
They offer these tips to keep your humidifier in tip-top shape:
- Use distilled or demineralized water to reduce bacterial growth.
- Change the water daily.
- Clean it every 3 days to help remove mineral deposits.
- Change the filter regularly.
- Keep the area surrounding the unit dry.
- Store the humidifier in a clean, dry place.
One final tip: "If you are not sure about using a humidifier," Dr. Morgan says, "ask your doctor for advice. If you don't want to bother with the maintenance and expense of a humidifier, consider a simpler option like taking a hot shower. This may be as effective for relieving dryness and breaking up mucus."
Read more: Does Drinking Water Help Chest Congestion?
Is This an Emergency?
- Janet Morgan, MD, Internal Medicine and Geriatrics, Cleveland Clinic, Beachwood, Ohio
- Cleveland Clinic: “How You Can Tell If You Need a Humidifier”
- U.S. Environmental Protection Agency: “Mold Course Chapter 2: Why and Where Mold Grows”
- Mayo Clinic: “Humidifiers: Air Moisture Eases Skin, Breathing Symptoms”
- National Heart, Blood, and Lung Institute: “Cough”
- American Academy of Allergy Asthma & Immunology: “Humidifiers and Indoor Allergies”
- Mayo Clinic: “Warm-Mist Versus Cool-Mist Humidifier: Which Is Better for a Cold?”