BOSTON, MA — If you have asthma, you need to know what to do when an attack begins. Adult Asthma: Your guide to breathing easier, a new Special Health Report from Harvard Medical School, presents a step-by-step guide to prepare adult sufferers to deal with asthma attacks:

Get away from the asthma trigger. Whether it’s cigarette smoke, a cat, or pollen, try to get away from whatever has triggered your asthma symptoms. Assess severity. You might recognize a severe attack based on how you feel. But measuring the strength of your exhale with a peak flow meter is the most precise way to assess severity. If your peak flow is less than half your best value, you are having a severe attack. Use a quick reliever. The fastest way to relieve an asthma attack is to use a quick-acting bronchodilator such as albuterol. If the medicine does not work, go to Step 4. Suppress inflammation. Quick-relief bronchodilators treat only one part of an asthma attack—the constricted muscles surrounding the bronchial tubes. Treating the other part—the overproduction of mucus—requires an anti-inflammatory medication, typically a corticosteroid. For a severe attack, increasing your usual inhaled steroid isn’t enough; you will also need to take prescription steroid tablets such as prednisone or methylprednisolone. Know when to call for help. Severe asthma attacks can be dangerous. If you follow your asthma action plan and don't feel improvement, get help immediately from family, friends, or a doctor, or call 911. Practice. Planning is important, but so is practice. This Special Health Report includes scenarios to help you rehearse your responses to different types of asthma attacks.