When it comes to controlling your asthma symptoms, one size does not fit all. Everyone with asthma suffers from inflammation and airway constriction, but symptoms are different for each person — and can change over time. Work with your doctor to master the three steps to better asthma control:

1. Track your symptoms. Keep an asthma symptom diary. At each visit, talk to your doctor about how severe your symptoms are and if they've changed since your last appointment.
2. Check your lung function. Use lung function tests to assess how well you can breathe.
3. Adjust your treatment. Based on your symptoms and lung function tests, you and your doctor can make changes to your treatment if needed.

Keep track of your asthma symptoms every day so that you and your doctor can review them at each appointment and adjust your treatment. Keep a written record of:

• Increased shortness of breath or wheezing (a whistling sound produced during exhalation)
• Disturbed sleep caused by shortness of breath, coughing or wheezing
• Chest tightness or pain
• Increased need to use a quick-relief inhaler containing a short-acting bronchodilator — a medication that opens airways by relaxing the surrounding muscles
• Decreased productivity at work, school, or at home due to asthma symptoms
• Increased asthma symptoms during exercise

To help control your asthma symptoms, you and your doctor may also use a common rating system based on the National Asthma Education and Prevention Program guidelines for grading asthma severity. This system uses four levels, based on two things that you can record in your asthma symptom diary:

1. How often and when you have symptoms
2. Your lung function test results

Where you fall on the asthma rating scale may change over time and with treatment. Assign yourself to the most severe category in which you currently have symptoms. For example, even though your symptoms may be generally mild, if you have serious flare-ups, you may have a more severe rating.

Lung function (pulmonary) tests can help you and your doctor judge how well you are controlling your asthma and may ward off flare-ups. One test you can use at home to keep track of how well you can breath. Another test you'll have during doctor visits.

Peak flow meter. By learning how to use a peak flow meter, you can help detect subtle changes in your airways before you notice symptoms. Your doctor can give you instructions on how to deal with low readings and prevent a flare up.A peak flow meter can be used at home to measure how well you can force air out of your lungs. It helps detect subtle narrowing of the airways before you notice symptoms. If the readings are lower than usual, it's a sign your asthma may be about to flare up. Your doctor can adjust your treatment based on the readings. Peak expiratory flow (PEF) tells you the fastest rate at which you force air out of your lungs.

Spirometer. A spirometer is used by a medical professional to measure narrowing of your bronchial tubes. This device measures the volume of air you can exhale after you've taken a deep breath. A spirometer also shows how quickly you can get air out of your lungs. This measurement is called forced expiratory volume-1 (FEV-1). Your doctor compares the result with the predicted result for people of the same age, sex, race and height who don't have asthma. This comparison is expressed as a percentage. Lower percentages indicate less lung power.

Here's how lung function measurements correspond to different grades of asthma severity:

By evaluating your symptoms and measuring your lung function, your doctor can decide how well your treatment is working.

Your doctor may suggest a change in treatment if:

• Your current medications are not controlling your asthma as well as possible
• Your medications are causing troublesome side effects
• You're using a quick-relief inhaler ("rescue" medication) too often

If you have persistent asthma, whether it's mild, moderate or severe, you're likely to need long-term control medications. Used properly, these medications can reduce or eliminate your need to use a quick-relief inhaler. These medications treat the underlying cause of asthma — inflammation — which leads to airway constriction that causes asthma signs and symptoms. The most effective long-term medications include:

• Inhaled corticosteroids. Examples include fluticasone (Flovent), budesonide (Pulmicort) and triamcinolone (Azmacort).
• Inhaled, long-acting beta-2 agonists. Examples include salmeterol (Serevent) or formoterol (Foradil).
• A combination of inhaled corticosteroids and long-acting beta-2 agonists. This approach requires using two inhalers or a combination inhaler such as Advair.
• Leukotriene modifiers. These drugs are taken in pill form, either alone or in conjunction with an inhaled corticosteroid. Examples include montelukast (Singulair) and zafirlukast (Accolate).
• Cromolyn (Intal) and nedocromil (Tilade). These medications, taken by inhalation, are sometimes used to treat mild persistent asthma.
• Theophylline (Uniphyl). This drug is taken in pill form, either alone or in conjunction with an inhaled corticosteroid. Although guidelines include it as an alternative to a long-acting beta-2 agonist in mild persistent and moderate persistent asthma, theophylline is rarely used in children.
• Oral corticosteroids. In some cases, severe asthma may require additional treatment with an oral corticosteroid such as prednisone or methylprednisolone.

Following is a summary of treatment recommendations for different levels of asthma severity for people ages 6 through adult. Younger children may need different treatment.

Track your symptoms, monitor your lung function and work with your doctor to adjust your treatment as needed. For treatment to work as well as possible, carefully follow your treatment plan. Keep a daily, written record of symptoms, triggers and medications. Go to every scheduled appointment, and talk with your doctor about your asthma at every visit. Asthma cannot be cured, but careful management can help you avoid asthma attacks and keep symptoms under control.

"Each person with asthma reacts differently to medication, the environment, triggers, and changing allergens that affect symptoms," says James Li, M.D., an asthma and allergy specialist at Mayo Clinic in Rochester, Minn., and the lead author of national asthma treatment guidelines. "Assessing these factors requires strong communication between you and your doctor on an ongoing basis to determine whether changes in treatment should be made."