Bronchodilators

Types and differences of bronchodilators

Some common bronchodilator medications include:

There are three types of bronchodilators:

Conditions treated

Bronchodilators are prescribed for a variety of conditions, including:

• Asthma. A condition in which airway passages become blocked or obstructed causing shortness of breath. Bronchodilators open the airways by relaxing the smooth muscles in these airways. They are among the most commonly used medications for asthma.
• Chronic bronchitis. Inflammation of the bronchial tube linings that lead to a persistent cough. Short-acting bronchodilators relieve coughing and shortness of breath.
• Chronic obstructive pulmonary disease (COPD). A progressive lung disease that decreases the ability of the lungs to perform ventilation. Bronchodilators smooth muscle constriction in the airways, increasing the flow of air.
• Mucus in the lungs. A build-up of mucus in the lungs causes a constriction of breathing passages and can lead to coughing. Bronchodilators work to diminish and thin mucus production.
• Emphysema. A condition in which the normal exchange of oxygen and carbon dioxide in the lungs is impaired due to damaged or collapsed air sacs. Bronchodilators improve air flow.
• Exercise-induced asthma (EIA). A temporary narrowing of the airways caused by excessive exercise that produces asthma-like symptoms. Bronchodilators administered before and after exercise keep the bronchial air passages open and prevent symptoms associated with this condition.
• Wheezing. A whistling sound caused by the friction of air going through narrowed airways. Bronchodilators widen the narrow passageways and relax the small tubes in the lungs, making breathing easier.

Conditions of concern

Patients should not take bronchodilators, unless prescribed by a physician, if they have been diagnosed with any of the following conditions:

• Heart or blood vessel disease. Bronchodilators may worsen these conditions.
• High blood pressure. Some types of bronchodilators may elevate blood pressure.
• Arrhythmias (abnormal heart rhythms). Some type of bronchodilators may worsen these conditions.
• Hyperthyroidism (overactive thyroid). Chances of bronchodilator side effects may be increased.
• Pheochromocytoma (a rare and usually benign cell tumor that produces adrenaline, raising blood pressure and heart rate). Bronchodilators may raise blood pressure and heart rate.
• Urinary problems. Bronchodilators may not be recommended for people with urinary problems because they may reduce urine output.
• Glaucoma. Bronchodilators may not be recommended for people with glaucoma.
• Viral illnesses. These conditions can alter the way a person's body responds to certain bronchodilators.
• Pregnancy. Some studies have shown birth defects in animals when given large doses of bronchodilators. Patients are advised to consult their physician.

Potential side effects

The form and severity of side effects will vary depending on the type of bronchodilator. High doses of short-acting beta2 agonists, for instance, have been associated with hypokalemia (low potassium levels in the blood, which can result in weakness) and abnormal heart rhythms.

A large clinical study found that the long-acting salmeterol drug was associated with a small, but statistically significant number of deaths in asthma patients. After investigating the drug, the Food and Drug Administration (FDA) updated the safety warnings on all long-acting beta2 agonists (LABA). The labels recommend that LABA medications not be the first medication used to treat asthma and that they should only be used as an additional therapy when a patient’s symptoms fail to respond to other asthma medications, such as low-to-medium dose inhaled corticosteroids.

Patients concerned about these warnings should NOT stop taking prescribed medication without first consulting their physician. The risk of untreated asthma is much higher than the risk of death from salmeterol.

Regular, frequent use of certain bronchodilators by a person with asthma may even worsen the condition. Patients taking bronchodilators are advised to call their physicians immediately if they experience any of the following symptoms:

• Chest pain
• Severe headache
• Severe vomiting
• Fever or chills
• Fast or pounding heartbeat
• Skin rash
• Hives
• Hoarseness
• Choking or difficulty swallowing
• Loud or high-pitched breathing
• Worsening of symptoms
• Swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, or lower legs

Less serious side effects should be brought to the attention of a physician and may include:

• Headache
• Anxiety, nervousness, agitation or hyperactivity
• Muscle cramps or tremors
• Coughing
• Dizziness or light-headedness
• Dryness or irritation of mouth or throat
• Unpleasant taste
• Nausea, stomachache or vomiting
• Pinkish-red saliva (isoproterenol only)
• Elevated blood pressure
• Diarrhea
• Difficulty urinating
• Tingling of the hands and feet
• Arching of the back

Patients should discuss all side effects with their physician because certain side effects indicate that the person is receiving too much medication. Physicians may conduct blood tests to determine if the patient is receiving the proper amount.

In addition, certain bronchodilators may cause temporary blurred vision if the medication comes into direct contact with the eyes.

Drug or other interactions

Patients should consult their physicians before taking any additional prescriptions, over-the-counter medications, nutritional supplements or herbal medications. Of particular concern to individuals taking bronchodilators are:

• Antihypertensives (medications to treat high blood pressure). Bronchodilator use may lessen the effectiveness of these drugs.
• Anti-arrhythmics (medications to treat abnormal heart beats). Bronchodilators used in conjunction with these drugs may lessen their effectiveness.
• Antibiotics (medications to treat bacterial infection). These medications may interfere with the function of bronchodilators.
• Antiseizure medications. Bronchodilator use may lessen the effectiveness of these drugs.
• Ulcer medications. These medications may interfere with the function of bronchodilators.
• Psychiatric medications. Use of some bronchodilators in conjunction with certain medications used to treat psychiatric disorders may lead to a potentially dangerous drop in blood pressure and/or rapid heartbeat.
• Smoke. Smoking or exposure to second-hand smoke can interfere with the way the body responds to certain bronchodilators.
• Caffeine. Coffee, tea, colas and other caffeinated drinks can change the effectiveness of certain bronchodilators.

Lifestyle considerations

Patients or caregivers of patients using bronchodilators need to know how to monitor and measure responses to these medications. The correct use and maintenance of devices such as nebulizers, peak flow meters and inhalers are very important.

Teenagers sometimes perceive a stigma associated with inhaler therapy because it can make them feel different, not well or not part of the group. Parents may wish to point out that many athletes with asthma use bronchodilators and such people are proof that it is still possible to participate and excel in physical activities. People any age taking bronchodilators are encouraged to discuss their concerns and activity levels with their physicians.

Some adolescents may deny having asthma or other breathing disorders that require bronchodilators and discontinue taking their medications. Caregivers need to be aware of this issue and monitor medication use until the adolescent is ready to manage his or her own care. Because bronchodilators are basically rescue medications, users need to have their medications with them at all times.

Pregnancy use issues

Certain bronchodilators are used to treat asthma in pregnant women, including albuterol, bitolterol, formoterol, metaproterenol and salmeterol. Although there have been no studies on birth defects in humans, and no reported cases definitively linking birth defects to bronchodilators, some animal studies involving bronchodilators report birth defects when given in doses many times higher than human doses.

Pregnant women who were given epinephrine under the skin have had more birth defects than expected in some studies, although the severity of the mother’s asthma may have contributed to this result.

The medicines fenoterol, isoproterenol, pirbuterol, procaterol and terbutaline have not been shown to cause birth defects in animal studies. Women taking bronchodilators who are pregnant or wish to become pregnant are encouraged to discuss potential benefits and risks with their physician.

It is not known at this time whether bronchodilators pass into the breast milk. Although most medicines pass into breast milk in small amounts, many of them are considered safe for nursing infants. Mothers who use bronchodilators and who wish to breastfeed are encouraged to discuss this with their physician.

Child use issues

Generally, bronchodilators are used on an as–needed basis when there is difficulty breathing or a child is having trouble with coughing or wheezing.

Studies performed to date have not demonstrated specific problems that would limit the usefulness of bronchodilators in children. However, isoetharine is not recommended for their use. Bronchodilators routinely prescribed for children include albuterol, bitolterol, levalbuterol, proventil, pirbuterol, terbutaline, levalbuterol.

Elderly use issues

The medicine salmeterol has been tested in a limited number of patients 65 years of age or older and has not been shown to cause different side effects or problems in older people than it does in younger adults.

The medicines albuterol, bitolterol, epinephrine, fenoterol, isoetharine, isoproterenol, metaproterenol, pirbuterol, procaterol, and terbutaline have not been studied specifically in older adults. It is not known whether or not they work exactly the same way as they do in younger adults or if they cause different side effects among the older adult population.