Chronic obstructive pulmonary disease (COPD) is a group of diseases that limit the flow of air into and out of the lungs. COPD includes chronic bronchitis and emphysema, most often caused by heavy, long-time cigarette smoking. COPD can also include chronic asthma.

Interstitial lung disease—sometimes called restrictive lung disease—refers to a group of lung problems. When you have interstitial lung disease, your lungs become inflamed and scarred. You may find it harder to take deep breaths. Or you may have a dry cough and mild chest discomfort.

Bronchitis occurs when the lining of the tubes leading to the lungs gets inflamed and begins making too much mucus. When this happens, your body must cough to clear out the extra mucus.

Coughing is a normal reflex that helps clear the lungs. Usually it is a minor annoyance, but sometimes a cough is a sign of a more serious condition. Most coughs are caused by postnasal drip, asthma, gastroesophageal reflux disease (GERD), or smoking.

An allergy is a reaction in the body to a normally harmless substance. Usually the immune system functions as the body's defense against invading bacteria and viruses. In most allergic reactions, the immune system is responding to a false alarm.

A rash is an inflammation or infection of the skin. Most people have had skin rashes at one time or another. Rashes can have a number of causes, including allergies, irritants, or illness.

Influenza is a viral respiratory infection of the nose, throat, and lungs that ranks as one of the most severe illnesses of the winter season (flu season is generally December through March). It is not the same as the "stomach flu." An estimated 10 to 20 percent of the population get influenza every year.

Pneumonia is an infection of the lungs. It usually affects children younger than 2, adults age 65 or older, and people with chronic health problems. There are many different types of pneumonia, which range in seriousness from mild to life threatening.

If you think you may have allergies, talk with your health care provider about getting tested.

Immunization against the viruses that cause influenza can prevent an infection or lessen its severity. Find out if you should be getting a flu shot each year.

Health care experts estimate that more than 37 million Americans are affected by sinusitis each year. When a minor cold or allergy attack goes bad, it can progress to sinusitis, also called a sinus infection. Sinus infections can be acute (three weeks or less), chronic (three to eight weeks, or longer) or recurrent (several acute attacks in a year).

Eczema is an inflammation of the skin that can have a variety of causes. There are acute and chronic forms of eczema. Two common types of eczema are atopic and contact dermatitis.

If you have asthma, does your dentist know? This is important for good oral health, especially if you use a corticosteroid inhaler.

Getting the flu can be serious business for people with asthma. That’s why it’s important to take steps to prevent it.

If you want to quit smoking but feel discouraged, don’t lose hope. Try taking a new perspective.