Asthma is inflammation and narrowing of the bronchial tubes. Air travels in and out of the lungs through these tubes.

The cause of asthma is not known. It does seem to run in some families. Current research suggests a combination of environment, genetics and biology may lead to asthma. Possible triggers of an asthma attack in a person with asthma include:

• Exercise
• Cold weather
• Viral illness
• Sinusitis
• Gastroesophageal reflux disease (GERD)
• Sulfites used in dried fruits and wine
• Medications, such as aspirin, ibuprofen, and beta-blockers
• Exposure to irritants or allergens, including:
  • Cigarette smoke, smoke from a wood-burning stove
  • Pet dander
  • Dust
  • Chemicals
  • Mold and mildew
  • Pollen
  • Smog or air pollution
  • Perfumed products

A risk factor is something that increases your chance of getting a disease or condition.

• Living in a large urban area
• Regularly breathing in cigarette smoke (including second-hand smoke)
• Regularly breathing in industrial or agricultural chemicals
• A parent who has asthma
• History of multiple respiratory infections during childhood
• Low birth weight
• Being overweight
• Gastroesophageal reflux disease (GERD)

Symptoms include:

• Wheezing
• Tightness in the chest
• Trouble breathing
• Shortness of breath
• Cough
• Chest pain
• Self-limited exercise, difficulty keeping up with peers

The doctor will ask about your symptoms and medical history and perform a physical exam:

Tests may include:

• Peak flow examination—blowing quickly and forcefully into a special instrument that measures your output of air
• Pulmonary function tests (PFTs)—breathing into a machine that records information about the function of your lungs
• Bronchoprovocation tests—lung function tests performed after exposure to methacholine, histamine, or cold or dry air, to stimulate asthma
  • Can help to confirm asthma in unclear cases, but not often used in a general practice setting
• Exhaled nitric oxide (a marker of airway inflammation)—to confirm the diagnosis and manage medications
• Allergy tests—usually skin or sometimes blood tests to find out if allergies are causing your symptoms

The treatment approach to asthma is four-fold:

• Regular assessment and monitoring
• Control of contributing factors (eg, gastroesophageal reflux and sinusitis)
• Patient education
• Medications

Often, you'll need to take more than one type of medication.

• Quick-acting beta agonists—(eg, inhaled albuterol or xopenex) relax your airways so that they become wider again
  • Also called rescue inhalers, are used to stop an acute episode of asthma, or "asthma attack"
• Long-acting beta agonists—(eg, inhaled salmeterol) used daily to prevent asthma attacks
  • Should not be used to try to stop an asthma attack in progress
  • A study showed that long-acting inhalers, like salmeterol, may increase the risk of a life-threatening asthma attack and asthma-related death if taken for more than three months, talk to your doctor about risks *
• Inhaled steroid—used daily to reduce inflammation in your airways, should not be used to try to stop an asthma attack in progress
• Cromolyn sodium or nedocromil sodium inhaler—used daily to prevent asthma flare-ups
  • May also be used just before exercise for exercise induced asthma
  • Should not be used to try to stop an asthma attack in progress
• Zafirlukast, Zileuton, and Montelukast—taken daily to help prevent asthma attacks
• Omalizumab (Xolair)—a monoclonal antibody against immunoglobulin E (IgE), used in conjunction with other medications
  • Given as a subcutaneous injection to treat allergic asthma
• Anticholinergic agents— inhaled medications, such as ipratropium, that function as a bronchodilator
• Corticosteroids—pills, injections, or intravenous (IV) medications given to treat acute flare-up of symptoms
  • Corticosteroid pills may be taken for a longer period of time if you have severe asthma that isn't responding to other treatments
• Theophylline—taken daily to help prevent asthma attacks

• Epinephrine—a shot given to stop an asthma attack