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Asthma Medications
The main categories of medications used in the management of asthma are controller medications and emergency or quick relief medications. Medications used in asthma therapy are directed toward reducing the main causes of asthma symptoms: bronchial constriction (bronchospasm), inflammation, and mucus production.
EMERGENCY/QUICK-RELIEF MEDICATIONS
Quick-relief medications work by temporarily relaxing the muscles surrounding the bronchi when they constrict during an asthma attack. These medications are referred to as “bronchodilators” because they dilate the bronchial tubes during an acute asthma attack. Once the bronchial tubes are opened, air is able to pass in and out of the lungs and normal breathing is restored. Anyone with asthma should have access to a quick reliever medication in case an asthma attack occurs.
Beta-2 agonists
Beta-2 agonists are the most commonly used most effective and rapid type of quick-relief medication. There are two main categories: Short-acting and long-acting.
Short-acting Beta-2 agonists start working in about 5-30 minutes, reaching peak effectiveness in about 30 minutes, and lasting up to 4-6 hours. Examples of short-acting Beta-2 agonists include: Albuterol (ProAir, Proventil, Ventolin) and levalbuterol (Xopenex).
Common ways short-acting Beta-2 agonists are used
- Given 20-30 minutes before exercise to prevent exercise-induced asthma
- Given as needed for asthma symptoms such as wheezing, coughing, chest tightness, or shortness of breath. These medications can be repeated as needed for severe wheezing or shortness of breath.
- In general, short-acting Beta-2 agonist medications should not be administered more than a few times daily for extended periods of time, as the child's body may not respond to them after a while. If your child requires short-acting beta-2 agonists more than twice a week or two nights per month, on a regular basis, have a discussion with your child's physician.
Long-acting Beta-2 agonists may start working in 5 minutes up to 2 hours (depending on the drug), reach peak effectiveness in 30-120 minutes, and keep working up to 12 hours. Examples of some long-acting Beta-2 agonists are: salmeterol (Serevent) and formoterol (Foradil). These should not be used as single agents in children with asthma.
Side-effects of Beta-2 agonists
Beta-2 agonists are related to a substance made naturally by the body called adrenaline. Like adrenaline, Beta-2 agonists can cause side effects such as muscle tremor, and a mild increase in heart rate, even when they are used properly. Levalbuterol (Xopenex) is a newer Beta-2 agonist medication that may produce fewer of these side effects.
Anti-cholinergic Medications
Anti-cholinergic medications work to relieve the symptoms of asthma by causing gradual and mild relaxation of the muscles that surround the bronchial tubes. Anti-cholinergic drugs work by using different chemical messages than the ones used by Beta-2 agonists. Some physicians use anti-cholinergic medications together with Beta-2 agonists to achieve more relaxation of constricted bronchial muscles than can be achieved with Beta-2 agonists alone. An example of an anti-cholinergic medication is ipratropium bromide (Atrovent)
Common uses of Anti-cholinergic medication
- Anti-cholinergic medication can be used to help relieve asthma attacks that usually aren't relieved well enough by Beta-2 agonists alone
Side Effects of Anti-Cholinergic medication
Anti-cholinergic medications rarely cause side effects. They occasionally are associated with a dry throat.
CONTROLLER MEDICATIONS
Controller medications help prevent asthma exacerbations, and reduce the severity of the child’s asthma. These medications control the substances in the body that cause inflammation in the child’s small airways during an asthma exacerbation. The inflammation during an asthma episode makes the airways even narrower, making it very difficult for air to pass in and out of the lungs. Because controller medications help control inflammation, they are also referred to as “anti-inflammatory” medications. Anti-inflammatory medications work by making the cells in the lungs less likely to release chemicals that cause inflammation. Less inflammation will make the lungs less sensitive to various “triggers” that can cause an asthma exacerbation. Because these medications prevent chronic inflammation, they are thought to reduce the complication of permanent lung damage (lung remodeling) caused by chronic asthma. These medications need to be taken on a daily basis to be effective. Higher doses may be prescribed for a short period during an asthma exacerbation.
Steroid-Type Controller Medications
Steroids act directly on the inflammatory cells that cause asthma. These medications are powerful and effective. The steroids used in the treatment of asthma are different from the anabolic steroids that have been abused by some athletes to "build up" muscles. Steroids used for the long-term control of asthma are usually inhaled. During an asthma attack, steroids given orally may be required.
Inhaled Steroid Medication
Inhaled steroids are made to go directly to where they are needed (the lungs), with less drug reaching any other part of the child's body. The inhalation of the steroid medication allows the drug to be extremely effective in preventing asthma inflammation while markedly reducing the risk of unwanted steroid-type side-effects. Inhaled steroids are used to prevent asthma attacks, and to improve asthma control. Because inhaled steroids usually take 1-6 weeks to reach peak effectiveness, inhaled steroids generally work best when taken every day. Many doctors also prescribe inhaled steroids in higher doses (double or triple the child's usual dose) at the first sign of an on-coming respiratory illness or asthma flare. Examples of inhaled steroid medications include: budesonide (Pulmicort), fluticasone (Flovent), beclomethasone (Qvar, Vanceril), mometasone (Asmanex) and triamcinolone (Azmacort).
Side Effects of Inhaled Steroids
The overwhelming majority of children using inhaled steroids experience no side effects at all.
A few children report dry mouth or minor throat irritation.
- Inhaled steroids can cause a yeast infection called thrush in the mouth. Thrush appears as small white patches in the mouth. If thrush occurs, it is usually treated with a special anti-yeast antibiotic. Thrush can be prevented by rinsing the mouth out with water (and then spitting out the water) after using the inhaled steroid inhaler
- Rarely, inhaled steroids can cause hoarseness. If your child develops a hoarse voice for no apparent reason (such as a cold), alert your child's physician.
- Some studies suggest that high dose inhaled steroids may cause a short-term decrease in height growth. However, it is difficult to determine the true effects of inhaled steroids on growth because severe, uncontrolled asthma can also affect growth. Most children on inhaled steroids grow normally. A few may even grow better because their asthma is better controlled. Additionally, daily use of inhaled steroids will reduce the need for oral steroids, which have more serious side effects when used frequently or in high doses (see "Oral Steroid Medication" section below). However, because of the possible link between inhaled steroid medication and slowed linear growth, children who take inhaled steroids should have their growth carefully monitored. Your physician will prescribe the lowest effective dose of inhaled steroid. If a growth delay is detected, most children will show rebound growth once their inhaled steroid medication is reduced. Dosage reduction should only be made under a physician's guidance, to prevent asthma recurrence.
- Inhaled steroids may cause minor changes in the balance of natural steroid hormones which are produced by the body. This has not proven to be of any clinical significance.
- A recent study suggested that the risk of glaucoma (increased pressure in the eye) may be increased in elderly people using prolonged high doses of inhaled steroids. Glaucoma is much more common in the elderly, and very rare in children. No studies indicate that children on inhaled steroids have a higher risk of developing glaucoma.
Oral Steroid Medication
Steroids can also be given by mouth or, in the hospital setting, injected (either through an intravenous needle or into the muscle). When given in these ways, steroids can powerfully reduce inflammation and are effective in controlling severe asthma attacks. Oral steroids are usually prescribed for 3-7 days. Examples of commonly prescribed oral steroids include: Prednisone, prednisolone (Orapred, prelone, Pediapred).
Side Effects of Oral Steroid Medication
- When used for short (3-7 day) periods, oral steroids can cause mood changes, increased appetite, acne and weight gain. Serious side effects are uncommon. Children who also have diabetes may need to adjust their insulin regimens.
- When used for long periods (many months or more), oral steroids can cause reduced growth, bone thinning, cataracts, hypertension, difficulty with physiologic stress (such as surgery), reduced ability to fight infections (especially chicken pox), difficulty controlling blood sugar, and weight gain. Because of the potential for these side effects, children who require long-term treatment with oral steroids require close monitoring by a physician.
Non-Steroid Controller Medications
Non-steroid controller medications work by reducing the inflammatory chemicals released by cells in the lungs. This reduces the inflammation present in the small airways of asthmatics and helps to prevent asthma attacks and improve asthma control. Examples of non-steroid controller medications are: cromolyn sodium (Intal), nedocromil sodium (Tilade), montelukast sodium (Singulair).Cromolyn sodium (Intal)
Intal works by stabilizing the cell wall of an inflammatory cell called a mast-cell. Stabilizing the cell wall of a mast cell prevents the cell's inflammatory chemicals from being released into the lungs which prevents inflammation. Intal is administered by nebulizer or inhaler. Intal works best in young children, and is given as a preventative medication, on a long-term, regular basis.
Side Effects of Intal: None.
Nedocromil sodium (Tilade)
Tilade is usually given on a long-term, regular basis to prevent asthma attacks and improve asthma control. It works in many, but not all asthmatics. It takes 1-6 weeks for Tilade to start working. Tilade is administered in a metered-dose-inhaler (puffer).
Side Effects of Tilade
Tilade almost never causes serious side effects;
- Some children are bothered by its taste
- Occasionally throat irritation or dryness may occur
- Tilade has been associated with headaches in some people
- Tilade has been associated with nausea in some people
Montelukast sodium (Singulair)
Montelukast sodium is a leukotriene modifier. Leukotrienes are chemicals released by lung cells, which play an important role in inflammation. Anti-leukotriene medications work by blocking the action or the release of the leukotrienes. Singulair may be adequate for some patients but most children are generally better controlled with inhaled steroids.
Side Effects of Anti-Leukotriene Medications
In general, studies have shown that side effects are very rare. Anti-leukotriene medications may cause headaches or stomach aches. Recent concerns about behavioral side effects of medications like montelukast have been disproved.
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