Quick Relievers - Medications To Treat Your Asthma: Asthma

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Quick relievers

When asthma causes shortness of breath, tightness in the chest, and troublesome coughing and wheezing, you want quick relief. At such times, fast-acting bronchodilators are the best option (see Table 1). These medicines relieve symptoms quickly by relaxing the muscles that surround the bronchial tubes and enabling the tubes to open wider.

Inhaled quick-acting bronchodilators begin to work within five minutes and continue providing relief for about four to six hours. You can also use your quick reliever 10 to 15 minutes before a predictable exposure to something that typically sets off your asthma, such as exercise or the cat at your neighbor's house. Quick relievers can often prevent tightening of the bronchial tubes that would otherwise occur. If your asthma symptoms are mild and infrequent, a quick reliever may be the only medication you need.

Beta-2 agonist bronchodilators

The most effective bronchodilators are known as beta-agonist medications because they work by stimulating molecular targets known as beta receptors. The first medication with beta-agonist properties, adrenaline (now more commonly called epinephrine), was developed in 1901. Years ago, a severe asthma attack was often treated with a shot of adrenaline. The treatment was effective but had serious side effects, including a racing, pounding heart; jitteriness; headache; and an increase in blood pressure. Epinephrine treatment is still occasionally used today in emergency situations. Inhaled epinephrine is also still available, as the active ingredient in Primatene Mist, a bronchodilator sold over the counter. Such over-the-counter bronchodilators are less effective, last for a shorter time, and have more side effects than modern prescription bronchodilators. (In January 2006 an FDA panel recommended a ban on Primatene Mist and other similar nonprescription inhalers that contain chlorofluorocarbons, or CFCs; see "CFC-free inhalers.")

In 1948, scientists developed a derivative of epinephrine, isoproterenol (Isuprel), which eliminated some of these side effects of epinephrine. If you have had asthma long enough, you may remember using an Isuprel Mistometer to relieve your asthma symptoms. However, overusing these bronchodilators to treat asthma attacks, while neglecting to treat the swelling and mucus plugging of the bronchial tubes, can result in disaster: severe asthma attacks and even death.

A major advance in asthma treatment was the development of more selective medications, known as beta-2 agonist bronchodilators, which work quickly, dilate the bronchial tubes effectively, and have fewer unpleasant side effects than the older medicines. The selective beta-2 agonist bronchodilators, such as albuterol, use a modified form of epinephrine and related chemicals to minimize cardiac side effects (caused by stimulation of beta-1 receptors) while maintaining bronchodilating effects (by stimulating beta-2 receptors).

Side effects of beta-2 agonists, if they occur, can include a pounding heart, a jittery feeling, and shakiness. The standard dose in adults is two inhalations (or "puffs"). Fortunately, for those adults who are particularly sensitive to side effects, one inhalation — with consequently fewer side effects — may suffice to open the breathing tubes. The medication works for about four to six hours. When it wears off, if you are still having asthma symptoms, you can take another dose (one or two puffs). In an asthma attack, when the bronchial tubes are severely narrowed, you can use your bronchodilator more often to get through a difficult period — as often as every 20 minutes.

Selective beta-2 agonists are available only by prescription. The most widely used is albuterol, available as a generic albuterol inhaler and also sold under the brand names Proventil, ProAir, and Ventolin. Other commonly prescribed beta-2 agonists include metaproterenol (Alupent), pirbuterol (Maxair), and levalbuterol (Xopenex). These medications all come in metered-dose inhaler devices small enough to fit in your purse or pocket, so they can be within easy reach whenever you need a puff or two to quiet your coughing or wheezing and restore your breathing to normal.

Using beta-2 agonists. Selective beta-2 agonists are available in tablets and liquid formulations, as well as in forms for inhalation. The inhaled medicine works faster, dilates the bronchial tubes better, and has fewer side effects than the tablet or liquid forms. To be effective, however, quick relievers need to be inhaled deeply into the bronchial tubes, not squirted onto the back of the throat. A holding chamber device known as a spacer can improve medication delivery. If you use a spacer with your regular controller medicine, you can use the same one with your quick reliever. Maxair has a unique breath-activated delivery device, called the Autohaler, that releases a pressurized spray of medication as soon as you begin to breathe in. The Maxair Autohaler cannot be used with a spacer. (For more information on the use of inhalers, see "Types of drug-delivery devices.")

Contrary to what was once thought — and taught — it is not necessary to use your quick-relief bronchodilator before inhaling your controller medication. In fact, you don't need to take a quick reliever on any regular schedule. Use it when you need to get rid of or prevent your asthma symptoms; don't use it when you don't have any symptoms.

At a medical visit, your health care provider will probably ask how often you have needed to use your quick-relief bronchodilator. This information is a useful measure of how active your asthma is. With good asthma control, you should need to use your quick-relief bronchodilator infrequently, ideally no more than once or twice a week.

Newer beta-2 agonists. Beta-2 agonist bronchodilators have advanced even further since the 1990s. Long-acting beta-2 agonist bronchodilators, effective for 12 or more hours, are now used as controller medications (see "Controller medications"). Another refinement was the creation of a purified form of albuterol known as levalbuterol (Xopenex). This medication is equally effective as a bronchodilator and it may cause slightly fewer side effects than albuterol, particularly jitteriness and heart racing. For most people, the advantages of levalbuterol over albuterol are small and not worth the significantly greater cost. However, in older people with heart disease such as angina or irregular heart rhythms, the lesser degree of heart stimulation caused by levalbuterol may be worth the expense. Levalbuterol is currently available both as a liquid for nebulization and in a metered-dose inhaler.

Other bronchodilators

For most people with asthma, the inhaled beta-2 agonist bronchodilators provide the best choice for quick relief of symptoms. There are some exceptions, however. Another type of bronchodilator may be appropriate in the following situations:

• You have serious and unstable heart disease. Under this circumstance, even a little extra stimulation of the heart might cause complications.

• You are taking a medication that might adversely interact with beta-agonists, such as a monoamine oxidase (MAO) inhibitor. Examples of MAO inhibitors include the rarely used antidepressants phenelzine (Nardil) and tranylcypromine (Parnate), and the anti-Parkinsonian medication selegiline (Eldepryl).

In these cases, the bronchodilator ipratropium (Atrovent), an anticholinergic medicine, may be used. Normally, ipratropium is used for the treatment of emphysema and chronic bronchitis, not for asthma. Compared with inhaled beta-2 agonist bronchodilators, it is weaker and slower. It takes 10 to 15 minutes to begin working, compared with fewer than five minutes for the fast-acting bronchodilators.

Another medication, theophylline, was the mainstay of bronchodilator therapy in the mid-1980s. Many people still rely on sustained-release theophylline in capsule or tablet form as a controller medication (see "Controller medications"). But theophylline has fallen from favor in the treatment of asthma, in part because of its frequent side effects and risk for toxicity, and in part because of the availability of better long-acting bronchodilators. Theophylline may cause nausea, diarrhea, and headache, as well as jitteriness and shakiness. More serious, if you take too large a dose of theophylline, there is a risk for seizures and irregular heart rhythms, which can be fatal. Theophylline overdoses have been responsible for intensive care unit admissions and even deaths. Many physicians consider it the most dangerous asthma medication. If you have been taking theophylline for years, you might want to consider switching to one of the newer long-acting inhaled bronchodilators. Talk with your doctor about options.

Last updated:	September 27, 2007