Having a cough is one of the most common reasons for seeing your doctor. Normal coughing is important to keep your throat and airways clear by getting rid of mucus or other irritating particles. However, a long-lasting (chronic) or severe cough may mean you have an underlying disease or disorder.

Coughs can be dry or "productive," which means that you are bringing up sputum or phlegm when you cough. An acute cough typically lasts no longer than 2 - 3 weeks. A chronic cough lasts longer than 4 weeks.

Many illnesses can cause cough. Acute coughs usually begin suddenly and are often due to a cold, flu, or sinus infection. Coughs from a lung infection such as bronchitis can start out suddenly and then linger on. Other common causes of chronic or ongoing coughs include asthma, allergies, chronic obstructive pulmonary disease (COPD from emphysema or chronic bronchitis, sinusitis with drainage into the throat, smoking cigarettes or exposure to secondhand smoke, pollutants, and gastroesophageal reflux disease (GERD). Some medications, such as ACE inhibitors taken to lower blood pressure, can cause chronic coughs in some people.

If your cough lasts more than 2 weeks, see your doctor to find out what may be causing it.

The symptoms that accompany your cough depend on whats causing it:

• A runny nose or nasal congestion, headache, or postnasal drip from chronic sinusitis (sinus inflammation), cold, or flu
• Wheezing from asthma
• Heartburn from GERD
• Fever, chills, night sweats from bronchitis, pneumonia, tuberculosis, or other lung infection
• Chest pain, shortness of breath, or swelling of your legs from fluid retention (called edema) due to congestive heart failure
• In rare cases, coughing up blood, which can be a sign of a serious illness such as lung cancer

• Respiratory tract infection: cold, flu, pneumonia, bronchitis, sinusitis
• Postnasal drip (from allergies or a cold)
• Certain medications called ACE inhibitors used to treat high blood pressure and heart disease:
  • Captopril (Capoten)
  • Benazepril (Lotensin)
  • Enalapril (Vasotec)
  • Lisinopril (Prinivil, Zestril)
  • Fosinopril (Monopril)
  • Ramipril (Altace)
  • Perindopril (Aceon)
  • Quinapril (Accupril)
  • Moexipril (Univasc)
  • Trandolapril (Mavik)
• Allergies
• Asthma
• Chronic obstructive pulmonary disease (COPD), which is from either emphysema or chronic bronchitis or both
• Aspiration, or foreign matter drawn into the lungs
• Heart failure
• Gastroesophageal reflux disease, where stomach acid backs up into the esophagus
• Lung cancer (rarely)
• Cigarette smoking or exposure to secondhand smoke
• Lung disease, such as bronchiectasis, interstitial lung disease, or tumors

Your doctor will take a detailed medical history, gathering information about the quality of the cough, how long you have had it, symptoms associated with the cough, etc. Your doctor will also do a thorough physical examination, paying particular attention to your nasal passages, throat, lungs, heart, and legs. Your doctor may order tests such as a sputum culture --if you have a productive cough that may be bacterial --an electrocardiogram (EKG), lung function tests, or x-rays of your chest or sinuses.

The goal of treatment is to not only soothe your cough but also treat the underlying cause.

If your doctor suspects a certain illness, your doctor may suggest you try certain medications that can help pinpoint the cause. For example, if your doctor thinks your cough is due to GERD, you may be prescribed medications to reduce your stomach acid. If your cough gets better, then the diagnosis will be correct.

Other medications that may be prescribed to either relieve your cough or treat the underlying problem include cough suppressants, inhalers, antibiotics, antihistamines, or expectorants. Some herbs and supplements may also be helpful in relieving your cough.

Lifestyle

Drink plenty of liquids to help thin the mucus in your throat.

If you smoke, stop.

Stay away from secondhand cigarette smoke and airborne irritants in your home or workplace.

If medications are causing your cough, your doctor may change your prescription. If you take an ACE inhibitor or other medication that seems to bring on your cough, do not stop taking it without your doctor's approval.

If you have allergies, you can take steps to avoid the allergic trigger, called an allergen. See also:Allergic Rhinitis

Sucking on cough lozenges or hard candy can help dry, tickling coughs. Never give these to a child under 3 years old because of the risk of choking.

Using a vaporizer or taking a hot shower can create moisture in the air and help soothe a dry throat.

Medications

Different drugs, listed below, may be used to either relieve your cough or treat the underlying condition.

• Cough medicines -- cough suppressants for a dry cough or expectorants for a wet, productive cough that brings up mucus are available over the counter and by prescription. Do not give over-the-counter cough suppressants to children under age 6 unless your doctor tells you to do so.
• Decongestants -- help open your nasal passages so you can breathe easier; they may help if your cough is due to postnasal drip. Some decongestants may contain pseudoephedrine, which can raise blood pressure. People with high blood pressure or enlarged prostate should not take drugs containing pseudoephedrine. Using nasal decongestant sprays and drops for more than 3 days in a row can cause "rebound congestion," where the nasal passages swell. Do not use decongestants if you have emphysema or chronic bronchitis. Decongestants are often combined in cold medicines with antihistamines, cough suppressants, and pain relievers. People with heart disease, high blood pressure, diabetes, or glaucoma should not take decongestants. Popular brands of decongestants include Sudafed, Afrin, and Neo-Synephrine.
• Antihistamines -- can temporarily relieve a runny nose by drying up nasal secretions; they may help if your cough is due to allergies. Non-drowsy antihistamines available over the counter include loratadine (Claritin), fexofenadine (Allegra), and cetirizine (Zyrtec).
• Bronchodilators -- increase airflow by opening airways and help make it easier to breathe; they may help if your cough is due to asthma or COPD.
• Corticosteroids -- reduce inflammation; either inhaled with an inhaler or taken by mouth, they are usually used to treat moderate-to-severe asthma or COPD.
• Nasal corticosteroids -- These prescription sprays reduce inflammation of the nose and help relieve sneezing, itching, and runny nose:
  • Beclomethasone (Beconase)
  • Fluticasone (Flonase)
  • Mometasone (Nasonex)
  • Triacinolone (Nasacort)

Nutrition and Dietary Supplements

Because supplements may have side effects or interact with medications, they should be taken only under the supervision of a knowledgeable health care provider.

For cough from respiratory infections, sinusitis, or allergies:

• Honey -- A 2007 study found that honey was more effective than over-the-counter cough medicines, including those containing dextromethorphan (or DM), at treating cough and easing sore throat. Honey can be mixed with an herbal tea or just warm water. Never give honey to an infant under the age of 1.
• Probiotics (Lactobacillus acidophilus) -- While probiotics won't directly relieve your cough, they may help underlying conditions. Some evidence suggests that Lactobacillus may help prevent colds and flu, and possibly reduce allergy to pollen. One study found that children in daycare centers who drank milk fortified with Lactobacillus had fewer and less severe colds. Another study of children in daycare found those who took a specific combination of Lactobacillus and Bifidobacterium had fewer flu-like symptoms. Several studies that examined probiotics combined with vitamins and minerals also found a reduction in the number of colds caught by adults, although it's not possible to say whether the vitamins, minerals, or probiotics were most responsible for the benefit. One small study suggests that Lactobacillus might help reduce allergic reaction to pollen. More studies are needed to say for sure whether it is effective. People with weakened immune system or who take drugs to suppress the immune system should not take probiotics except under a doctor's supervision.
• Quercetin -- Quercetin is a flavonoid, a plant pigment responsible for the colors found in fruits and vegetables. In test tubes, it inhibits the production and release of histamine, which causes allergy symptoms, such as a runny nose and watery eyes. Its often combined with bromelain, a supplement made from pineapples. However, there is not yet much evidence that quercetin would work the same way in humans. More studies are needed. Quercetin interacts with a number of medications, including some antidepressants, cyclosporine (Neoral, Sandimmune), metoprolol (Lopressor, Toprol XL), ondansetron (Zofran), risperidone (Risperdal), tramadol (Ultram), midazolam (Versed), omeprazole (Prilosec), lansoprazole (Prevacid), propranolol (Inderal), fexofenadine (Allegra), and warfarin (Coumadin), among others. To be safe, ask your doctor before taking quercetin if you take any medication or if you are pregnant or breastfeeding.
• Spirulina -- Preliminary test tube and animal studies suggest that spirulina, a type of blue green algae, may help protect against harmful allergic reactions. Spirulina blocks the release of histamine, which contributes to allergic symptoms. Research on people is needed. People with autoimmune diseases, such as rheumatoid arthritis or lupus, or those who take medications to suppress their immune systems should ask their doctor before taking spirulina.
• Bromelain -- Some studies show that bromelain may help reduce symptoms of sinusitis and relieve swelling and inflammation caused by allergies (hay fever). Not all studies show a benefit, however. It is often combined with quercetin. Bromelain may increase the risk of bleeding, so people who take blood-thinners such as aspirin or warfarin (Coumadin) should not take bromelain without talking to their doctor first. Taking bromelain with ACE inhibitors may cause a dangerous drop in blood pressure (hypotension). Bromelain may interact with some antibiotics, including amoxicillin and tetracycline. People who are allergic to pineapple should not take bromelain.

Herbs

The use of herbs is a time honored approach to strengthening the body and treating disease. Herbs, however, can trigger side effects and can interact with other herbs, supplements, or medications. For these reasons, herbs should be taken with care, under the supervision of a health care practitioner.

• Peppermint (Mentha x piperita) -- Peppermint is widely used to treat cold symptoms. Its main active agent, menthol, is a good decongestant. Menthol also thins mucus and works as an expectorant, meaning that it helps loosen and break up mucus. It is soothing and calming for sore throats and dry coughs as well. Don't use peppermint or menthol with infants. Do not take peppermint oil by mouth.
• Eucalyptus (Eucalyptus globulus) -- Like peppermint, eucalyptus is used in many remedies to treat cold symptoms, particularly cough. It can be found in many lozenges, cough syrups, and vapor baths throughout the United States and Europe. Ointments containing eucalyptus leaves are also applied to the nose and chest to relieve congestion and loosen phlegm. Eucalyptus oil should not be taken by mouth because it can be poisonous.
• Marshmallow (Althea officinalis) -- Although there isnt any scientific evidence that it works, marshmallow has been used traditionally to treat sore throat and cough. It contains mucilage, which helps coat the throat and act as a cough suppressant.
• Slippery elm (Ulmus fulva) -- Slippery elm may help ease sore throat and cough, and has been used traditionally for this purpose, although scientific evidence is lacking. Like marshmallow, it contains mucilage. Slippery elm may affect how your body absorbs some medications, so wait at least one hour after taking any other medications before taking slippery elm. Pregnant or breastfeeding women should avoid slippery elm.
• Licorice (Glycyrrhiza glabra) -- Licorice root is a traditional treatment for sore throat and cough, although scientific evidence is lacking. Licorice interacts with a number of medications, so ask your doctor before taking it. People with high blood pressure, kidney disease, liver disease, or heart disease, women who are pregnant or breastfeeding, and those who take blood-thinners such as aspirin or warfarin (Coumadin) should not take licorice.
• Lobelia (Lobelia inflata) -- Also called Indian tobacco, lobelia has a long history of use as an herbal remedy for respiratory problems including cough. It is an expectorant, meaning that it helps clear mucus from your lungs. However, lobelia can be toxic and should only be used under a doctor's supervision.
• Mullein (Verbascum densiflorum) -- Mullein is an expectorant, meaning it helps clear your lungs of mucus. Traditionally, it has been used to treat respiratory illnesses and coughs with lung congestion. However, there aren't any scientific studies to say whether it works.
• Sundew (Drosera spp.) -- Sundew has traditionally been used as a cough suppressant, although there aren't any scientific studies to say whether it works. It is often used in Europe to treat dry coughs.
• Stinging nettle (Urtica dioica, 600 mg per day for 1 week) -- Stinging nettle has been used traditionally for treating a variety of conditions, including allergies (hay fever). But studies so far are lacking. Only one small study suggested that stinging nettle might help relieve symptoms of hay fever, including cough. Pregnant women and young children should not take stinging nettle. Talk to your doctor before taking stinging nettle if you take blood pressure medication, blood thinners, diuretics (water pills), or have diabetes.
• Thyme (Thymus vulgaris) -- Thyme has traditionally been used to treat respiratory illnesses such as bronchitis and to treat cough. Two preliminary studies suggest that thyme may help treat acute bronchitis and relieve cough. Thyme is approved by the German Commission E to treat those conditions. Thyme oil is considered toxic and should not be taken by mouth. Thyme may increase the risk of bleeding, especially if you also take blood-thinners such as aspirin, clopidogrel (Plavix), or warfarin (Coumadin).

Homeopathy

Although very few studies have examined the effectiveness of specific homeopathic therapies, professional homeopaths may consider the following remedies for the treatment of coughs based on their knowledge and experience. Before prescribing a remedy, homeopaths take into account a person's constitutional type. A constitutional type is defined as a person's physical, emotional, and psychological makeup. An experienced homeopath assesses all of these factors when determining the most appropriate treatment for each individual.

Aconitum-- taken within the first 24 hours of a cough that comes on suddenly, particularly if symptoms develop following exposure to cold weather; this remedy is considered most appropriate for individuals with a hoarse, dry cough who complain of dry mouth, thirst, restlessness, and symptoms that worsen in the cold or when the individual is lying on his or her side.

Antimonium tartareicum-- for wet, rattling cough (although the cough is usually too weak to bring up mucus material from the lungs) that is accompanied by extreme fatigue and difficulty breathing; symptoms usually worsen when the person is lying down; this remedy is generally used during the later stages of a cough and is particularly useful for children and the elderly.

Bryonia-- for dry, painful cough that tends to worsen with movement and deep inhalation; this remedy is most appropriate for individuals who are generally thirsty, chilly, and irritable.

Causticum-- for laryngitis and a cough that cannot dislodge mucus in the chest and may cause the individual to leak urine during coughing fits; symptoms tend to improve with sips of cold water but worsen with cold air.

Drosera-- for dry, spasmodic cough accompanied by sharp chest pain and a tickling sensation in the throat that may cause the individual to gag, choke or vomit; the individual may be hoarse or may perspire in the evenings and symptoms may worsen when the individual is lying down.

Ipecacuanha-- for deep, wet cough, often with gagging, nausea, and vomiting; this remedy is especially useful for bronchitis in infants.

Phosphorous-- for chest tightness associated with a variety of coughs, particularly a dry, harsh cough with a persistent tickle in the chest and significant chest pain; symptoms tend to worsen in cold air and when the individual is talking; this remedy is most appropriate for individuals who are often worn out and exhausted, suffer from unnecessary anxiety (even fear of death), and require a lot of reassurance.

Rumex-- for dry, shallow cough that begins with a tickling sensation in the throat or with the inhalation of cold air.

Spongia-- for harsh, barking cough without mucus production; this type of cough is associated with a tickling in the throat or chest; it tends to worsen when the person is lying down and improves when the individual eats or drinks warm liquids; this remedy is often used if a trial of Aconite was not successful.

To successfully treat your cough, it is important to find out the underlying condition that's causing it.

Warnings and Precautions

Call your doctor right away if you have any of the following characateristics to or symptoms accompanying your cough:

• Violent cough that begins suddenly
• High pitched sound (called stridor) when inhaling
• Cough that produces blood
• Cough in an infant less than 3 months old
• Shortness of breath or difficulty breathing
• Fever
• Abdominal swelling
• Unintentional weight loss
• Thick, foul-smelling, green phlegm

Prognosis and Complications

Most causes of cough are very treatable. The prognosis depends on what is causing your cough.

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