What Is Asthma?
Asthma is a chronic lung disease that makes breathing difficult. It causes symptoms such as shortness of breath, wheezing, cough, and chest tightness (some people get all of these symptoms, while others may only have cough, for example). Asthma varies widely in its severity. To the mild asthmatic it can be little more than an annoyance. For the moderate asthmatic, it can definitely affect the way they go about their routine activities. For the severely affected, asthma can be a life-threatening disease.
As part of the asthma disease process the bronchial tubes, the airways through which oxygen comes into the lungs, are chronically inflamed and swollen. Also, the interior of the bronchial tubes can be obstructed by thick mucus and narrowed because of thickened muscles surrounding the tubes. These changes result in difficulty in the movement of air to the lungs and the symptoms mentioned above.
Researchers have looked at tissue biopsies of asthmatic bronchial tubes under the microscope and found their lining damaged and their walls thickened because of leaky blood vessels, infiltration of white blood cells with the toxic chemicals they release, overgrowth of mucus secreting cells, among other findings. There may be different reasons why this inflammation occurs depending on a variety factors particular to each asthmatic sufferer. In some people a major cause is exposure to allergens (see What is an Allergy?), while in others the cause of the inflammation is unknown.
This inflammation leads to “twitchiness” of the muscles surrounding the bronchial tubes – put another way the inflammation leads to “airway hyperresponsiveness” or “airway hyperreactivity.” Consequently, if an asthmatic is exposed to an irritant (cold air, cigarette smoke, exercise, allergens) this twitchiness can lead to clamping down and narrowing of the airways. This results in the typical asthmatic symptoms. For those with more than mild asthma, this can occur without any irritant exposure or exercise.
In summary, asthma is a chronic disease of inflammation of the airways that leads to decreased air movement to the lungs. It is the result of some known (allergens, occupational exposures) and some unknown factors. Even though some younger asthmatics can go into remission over time, there is currently no cure for asthma. However, in the great majority of sufferers that disease can be controlled very well with proper medical treatment and minimal side effects.
Frequently Asked Questions on Asthma
Asthma is a chronic lung disease that makes breathing difficult. It causes symptoms such as shortness of breath, wheezing, cough, and chest tightness (some people get all of these symptoms, while others may only have cough, for example). It is the result of some known (allergens, occupational exposures) and some unknown factors.
The following information is provided to answer commonly asked questions about Asthma.
- What are the symptoms of asthma?
- How is asthma diagnosed?
- What causes asthma?
- Is asthma a serious disease?
- What different kinds of asthma medications are used?
- What are bronchodilators?
- How are anti-inflammatory drugs used in asthma?
- What about Xolair (anti-IgE) for asthma?
- Should I continue to take asthma medications during my pregnancy?
- Should I limit my activity because I have asthma?
- How do I know if my asthma is serious?
- Do allergy injections (allergen immunotherapy) work for asthma?
- What about theophylline-based medications?
- What about the leukotriene modifier tablets?
- I have heard that antihistamines are bad for asthmatics – is this true?
- What different medical conditions can complicate asthma?
- Will my child inherit my asthma or allergies?
- What is the treatment for exercise-induced asthma?
- Can I go SCUBA diving if I have asthma?
Typical symptoms include chest tightness, shortness of breath, coughing, and wheezing. The symptoms can be brought on by certain exposures (irritants, allergens, exercise), or they can be persistent.
How is asthma diagnosed?
The diagnosis is best done by a visit to the doctor. The diagnosis is based on typical symptoms, the patient’s medical and family history, physical exam, and often with breathing tests, such as spirometry.
What causes asthma?
Good question! We know that allergies (e.g. airborne pollens and dust mites). contribute to the asthma of many children and adults. But there are many people who have asthma and no allergies at all. Although we are not sure of all the fundamental causes of asthma, we believe that both environmental and genetic factors play a role in the inflammation of the airways typical of asthma.
Is asthma a serious disease?
Yes, it can be. Asthma is unique because the intensity of disease varies widely. Asthma can be merely an inconvenience in one person, and it can be a potentially life-threatening disease in another. A given individual may fall anywhere between these two points. Also, an asthmatic may move up or down this scale during the course of a lifetime – some lucky patients go into remission as they age. The overwhelming majority of asthmatics can be effectively be treated with medications (as well as anti-allergy measures) with minimal, if any, side effects.
What different kinds of asthma medications are used?
There are many different types and brands of asthma drugs on the market. We believe it is helpful to classify the drugs to help understand how they are used. The two main types are bronchodilators and anti-inflammatory medications (steroid/cortisone-type medications). Two other types of medications – Leukotriene modifiers and phosphodiesterase inhibitors (e.g. theophylline) – are difficult to classify since they seem to have properties of both bronchodilators and anti-inflammatory medications.
“Reliever” medications, which are fast-acting bronchodilators, open up the lungs immediately. They are used “as needed,” when symptoms occur. Examples would include forms of albuterol. These are sometimes referred to as “rescue” or “emergency inhalers,” but we believe these are misleading terms. It doesn’t have to be an emergency for you to use these drugs. Simply take them when you are uncomfortable with your breathing. All asthma patients must have a reliever medication prescribed to them. They come as inhalers, or in liquid form to be used in a nebulizer machine.
“Controller” medications should be prescribed when an asthma patient has symptoms occurring more than once or twice a week on average. Some doctors prefer the term “maintenance” medications. They are taken regardless of how you feel and on a routine basis to help prevent asthma attacks. There are several types including inhaled steroids, leukotriene modifier tablets, as well as combination inhalers containing both a steroid and a long-acting bronchodilator.
What are bronchodilators?
Bronchodilators are medications that dilate (open up) the bronchial tubes to permit easier breathing and relieve symptoms. There are short-acting bronchodilators that are used for quick relief of asthma symptoms. Most doctors instruct patients to use them as needed – the moment that asthma symptoms arise. In children, bronchodilators are sometimes used on a regular basis, because kids may not let their parents know when they are having symptoms.
Long-acting bronchodilators keep the bronchial tubes dilated over many hours. Important to know, however, is that these medications may take a while (maybe an hour or so) to start working. They should never be used for quick relief of asthma symptoms. That is, they are prescribed as maintenance medications – they are taken daily without regard for the symptoms the patient is having at that particular moment. This type of long-acting bronchodilator should only be used in conjunction with daily inhaled steroid medications when treating asthma. Importantly, the patient must also have a short-acting bronchodilator for quick relief. Long-acting bronchodilators are included in combination inhalers with steroids.
Theophylline and leukotriene modifiers are considered by some to be long-acting bronchodilators also, but have been used as the sole medication in some patients.
How are anti-inflammatory drugs used in asthma?
The main type of anti-inflammatory is inhaled steroids. Even though the word “steroid” sounds scary, these drugs, especially at low dosages, are safe for use even in children. Leukotriene modifier tablets also may have some anti-inflammatory effects. They should be used as daily, maintenance medications as they do not result in immediate relief of symptoms. These anti-inflammatory medications, especially the steroids, may prevent the permanent damage to the lungs that experts believe is occurring over many years in the uncontrolled asthmatic.
Consequently, US and international expert guidelines for the treatment of asthma recommend that any asthmatic experiencing symptoms more that twice a week should be treated with maintenance medications like inhaled steroids. These recommendations also apply to children and pregnant women. For most patients, inhaled steroids are the most effective type of medications, and they are considered to be extremely safe drugs when given in low doses.
There is a little concern about long-term inhaled steroids in children because of possible growth delay. However, most of the experts believe that if the asthma is serious enough, it is well worth the small risk of treating with inhaled steroids. There is also some concern of the effect of these medications on bone density in older individuals.
The oral form of steroids (e.g. prednisone) should be reserved for two situations because long-term use can have serious side effects:
For short courses (5 – 10 days) used in asthma exacerbations – when a patient is having to use their bronchodilator very frequently or when the asthma is interfering with their daily routine (nighttime awakenings, missing work or school).
Chronic, daily use of oral steroids is reserved for the most severe asthmatic when all other types of asthma drugs have been tried. We believe that any asthmatic taking chronic, daily oral steroids should definitely be followed by an asthma specialist.
What about Biologic treatments for asthma?
Anti-IgE treatment has been around for several years. It is used in the more severe allergic asthmatics who don’t respond to the usual asthma treatment. It is given as an injection once or twice a month. In carefully selected patients, it can be dramatically effective. It is usually only given in asthma specialists offices, as opposed to a primary care office.
Should I continue to take asthma medications during my pregnancy?
YES! Although your doctor may want to switch which drugs you are taking, you must continue to take appropriate treatment during pregnancy. Very effective anti-asthma drugs are available that are considered to be safe for pregnancy. The fetus depends on his mother’s lungs for oxygen. If your OB/GYN doctor refuses to put you on medications to control your asthma during pregnancy, you may want to get a second opinion or have an asthma specialist speak to them.
Should I limit my activity because I have asthma?
No and yes. First of all, asthma is very treatable. If you can’t do your normal activities or are unable to exercise as much as you want, then there is something wrong with your asthma treatment program. There are Olympic athletes who have significant asthma! In general, there are very few activities that asthmatics need to avoid (e.g., SCUBA, see below).
So, having asthma is no excuse for being a couch potato. It is a shame that some asthmatic children are kept from physical education classes or recess because they are not being treated appropriately for their asthma. In fact, some experts theorize that inactivity can, over the long run, worsen asthma.
If your asthma is not under control, then you should limit your activity briefly until you can get treated adequately by your doctor. It is the rare asthmatic who has such severe symptoms that they must limit their activity despite maximal medical treatment.
How do I know if my asthma is serious?
Most agree that you should consider getting specialist care for your asthma in the following instances:
You have been hospitalized (kept overnight in the hospital) for your asthma in the recent past.
You are often taking oral steroids (pills or syrup) for your asthma.
You are chronically taking more than 2 different types of medications for your asthma.
You have been to the emergency room for asthma more than once or twice in the past year.
You are going through more than one bronchodilator inhaler each month.
You are missing work, school, or not sleeping well regularly because of the asthma.
Whenever you feel like your asthma is not controlled.
Do allergy injections (allergen immunotherapy) work for asthma?
Scientific evidence shows that immunotherapy does improve asthma in allergic patients, as shown in a recent meta-analysis (a statistic analysis of many studies pooling all the information from hundreds or thousands of patients) in the pulmonary journal The American Review of Respiratory and Critical Care Medicine. Although some recent studies have shown that immunotherapy is not necessarily better than full medication treatment for asthma, these allergen injections will often lessen the amount of medication needed to control asthma. These injections are a great choice for those patients who don’t comply well with medications, those who don’t want to rely too much on medication, and especially for those patients who also have allergic rhinitis (“hay fever”). Allergen immunotherapy in appropriately selected patients should improve allergic rhinitis and asthma symptoms, and decrease the requirement for medicating both conditions.
What about theophylline-based medications?
This type of oral medication is effective in treating asthma, particularly nighttime asthma. Some asthma specialists believe that the side effects of these medications have made them a bit obsolete, especially since long-acting bronchodilator inhalers are now available.
What about the leukotriene modifier tablets ?
These oral medications have also been shown to be effective in treating asthma. Doctors use them in mild to moderate asthmatics to replace or add to anti-inflammatory medications (see above). They might be particularly beneficial for patients who are already on high doses of inhaled steroids, those who are aspirin sensitive (“allergic”), and those who have nasal polyps.
I have heard that antihistamines are bad for asthmatics – is this true?
I consider this an “old doctor’s tale.” Some of the newer antihistamines have been shown in studies to be very safe in asthmatics – perhaps even making the asthma improve. There were studies done many years ago that suggested that older antihistamines (like some of the over-the-counter drugs available today) could worsen asthma. A recent meta-analysis showed that antihistamines do not increase asthma symptoms or decrease lung function in asthmatics. Indeed, many asthmatics have allergies, and we don’t believe that they should be denied the newer prescription antihistamines.
What different medical conditions can complicate asthma?
If your asthma is not well-controlled on a reasonable amount of medication, then you and your doctor should consider the following conditions which may worsen or mimic asthma symptoms:
Sinusitis (sinus pain, thick post-nasal drip, nagging cough)
Gastric reflux (usually manifested by heartburn, but sometimes only by cough)
Certain hypertension medications (ask your doctor if you are on a beta-blocker or ACE inhibitor)
Vocal cord dysfunction (a disorder of the larynx than involves involuntary spasm of the vocal cords)
Other lung disorders besides asthma
Will my child inherit my asthma or allergies?
There is no doubt that there is a genetic component to allergies and asthma. Chances are that the tendency to be allergic will be passed down the line if both parents are allergic. However, the manifestations of the allergy are not necessarily inherited. That is, you may have asthma and your child may end up with allergic rhinitis (“hay fever”). Also, you may be allergic to cats, where your child may only wind up allergic to dust mites. If you are allergic, it is a good idea to limit your child’s exposure to common indoor allergens as soon as they are born – a strategy that may prevent them from developing problems with allergy as they grow up. This might entail removing carpeting and/or using plastic mattress encasements (for dust mites) or even finding a new home for the family cat (or at least keeping it out of the child’s bedroom).
What is the treatment for exercise-induced asthma?
Pre-exercise bronchodilators (e.g. albuterol), Singulair (Montelukast) and inhaled steroids, are recommended for the prevention of exercise-induced asthma symptoms. Usually, they are taken well before the exercise occurs. Albuterol or another fast-acting bronchodilator should be used for acute symptoms. In general, the better your asthma is controlled, the less problem you will have with exercising.
Can I go SCUBA diving if I have asthma?
This is another controversial question. Most asthma specialists would say that if you currently have symptomatic asthma, even if it is well controlled on medication, you shouldn’t dive. Some experts even go as far to state that even those with asthma in remission shouldn’t dive. There is still a lot of research to be done in this area.