The best way to treat a cough is to treat its cause. However, sometimes the cause is unknown. Other treatments, such as medicines and a vaporizer, can help relieve the cough itself.
                
Treating the Cause of a Cough
                
Acute and Subacute Cough
                
An acute cough lasts less than 3 weeks. Common causes of an acute cough are a common cold or other upper respiratory infections. Examples of other upper respiratory infections include the flu, pneumonia, and whooping cough. An acute cough usually goes away after the illness that caused it is over.
                
A subacute cough lasts 3 to 8 weeks. This type of cough remains even after a cold or other respiratory infection is over.
                
Studies show that antibiotics and cold medicines can't cure a cold. However, your doctor may prescribe medicines to treat another cause of an acute or subacute cough. For example, antibiotics may be given for pneumonia.
                
Chronic Cough
                
A chronic cough lasts more than 8 weeks. Common causes of a chronic cough are upper airway cough syndrome (UACS), asthma, and gastroesophageal reflux disease (GERD).
                
"UACS" is a term used to describe conditions that inflame the upper airways and cause a cough. Examples include sinus infections and allergies. These conditions can cause mucus (a slimy substance) to run down your throat from the back of your nose. This is called postnasal drip.
                
If you have a sinus infection, your doctor may prescribe antibiotics. He or she also may suggest you use a medicine that you spray into your nose. If allergies are causing your cough, your doctor may advise you to avoid the substances that you're allergic to (allergens) if possible.
                
If you have asthma, try to avoid irritants and allergens that make your asthma worse. Take your asthma medicines as your doctor prescribes.
                
GERD occurs if acid from your stomach backs up into your throat. Your doctor may prescribe a medicine to reduce acid in your stomach. You also may be able to relieve GERD symptoms by waiting 3 to 4 hours after a meal before lying down, and by sleeping with your head raised.
                
Smoking also can cause a chronic cough. If you smoke, it's important to quit. Talk with your doctor about programs and products that can help you quit smoking. Also, try to avoid secondhand smoke.
                
Many hospitals have programs that help people quit smoking, or hospital staff can refer you to a program. The Health Topics Smoking and Your Heart article and the National Heart, Lung, and Blood Institute's "Your Guide to a Healthy Heart" booklet have more information about how to quit smoking.
                
Other causes of a chronic cough include respiratory infections, chronic bronchitis, bronchiectasis, lung cancer, and heart failure. Treatments for these causes may include medicines, procedures, and other therapies. Treatment also may include avoiding irritants and allergens and quitting smoking.
                
If your chronic cough is due to a medicine you're taking, your doctor may prescribe a different medicine.
                
Treating the Cough Rather Than the Cause
                
Coughing is important because it helps clear your airways of irritants, such as smoke and mucus (a slimy substance). Coughing also helps prevent infections.
                
Cough medicines usually are used only when the cause of the cough is unknown and the cough causes a lot of discomfort.
                
Medicines can help control a cough and make it easier to cough up mucus. Your doctor may recommend medicines such as:
                
Prescription cough suppressants, also called antitussives. These medicines can help relieve a cough. However, they're usually used when nothing else works. No evidence shows that over-the-counter cough suppressants relieve a cough.
                
Expectorants. These medicines may loosen mucus, making it easier to cough up.
                
Bronchodilators. These medicines relax your airways.
                
Other treatments also may relieve an irritated throat and loosen mucus. Examples include using a cool-mist humidifier or steam vaporizer and drinking enough fluids. Examples of fluids are water, soup, and juice. Ask your doctor how much fluid you need.
                
Cough in Children
                
No evidence shows that cough and cold medicines help children recover more quickly from colds. These medicines can even harm children. Talk with your child's doctor about your child's cough and how to treat it.