Asthma: Diagnosis, Tests and Medications

Medically Reviewed by Dr. K on 15 April 2021

Table of Contents :


  1. Asthma Diagnosis and Tests
  2. Physical Exam
  3. Medical History
  4. Lung Function Tests
  5. Types of Lung Function Tests
  6. Other Tests 
  7. Sinuses
  8. Tests for Other Conditions
  9. Severity of Asthma
  10. Asthma Medications 
  11. Long-Term Control Medications
  12. Quick-Relief Asthma Drugs
  13. Inhalers, Nebulizers and Pills  
  14. Over-the-Counter Asthma Treatments
  15. Allergy Shots and Asthma
  16. Asthma Medication Frequency
  17. Asthma Medication Guidelines


Asthma Diagnosis and Tests


Your doctor will conduct tests to determine if you have asthma. Certain tests assess how well your lungs function. Others can verify whether you are allergic to mould, pollen, or other substances. All of these asthma tests assist your doctor in determining whether you have asthma and any associated conditions, such as allergies, GERD, or sinusitis.


Physical Exam


Your doctor will begin with a physical examination. They are going to:

  • Examine your nasal passages, throat, and upper airways.
  • Listen to the breathing with a stethoscope for a whistling sound.
  • Examine your skin for signs of allergy, such as eczema or hives.


They will also ask a few questions about asthma symptoms such as:


  • Wheezing
  • Coughing
  • Breathing problems
  • Chest tightness

Medical History


After that, your doctor will ask about your symptoms and overall health to determine whether asthma or something else is causing your problem. Some examples of questions could be:

  • What are your symptoms?
  • When do you have experience with these symptoms?
  • What appears to trigger them? What about cold air, exercise, or allergies?
  • Do you have hay fever or allergies?
  • Do you have a family history of hay fever, asthma, or allergies?
  • What other health conditions do you have?
  • What medications are you taking?
  • Do you frequently come into contact with tobacco smoke, pets, dust, or chemicals in the air?
  • What do you do for a living? 


Lung Function Tests

Lung function tests determine how well your lungs are working. They are used by doctors to diagnose asthma and track its progression. As you will not always be able to say if your asthma is under control only by looking at your symptoms, monitoring your asthma with lung function tests is beneficial.

Lung function examinations are usually performed in an exam room with special instruments that assess lung function. The tests are likely to be performed by a professionally qualified respiratory therapist or technician.

Inquire with your doctor if there is something you can do to plan for your lung function exams. For example, you may require medication adjustment. You should also avoid heavy meals, smoking, and any irritants or other substances that could cause an asthma attack.

Types of Lung Function Tests

These lung function tests are frequently used to diagnose and monitor individuals who suffer from asthma:

  • Spirometry is the most common. It’s an easy, painless method of checking your lungs and airways. You inhale deeply and exhale into a hose attached to a spirometer. It keeps track of how much air you expel (referred to as forced vital capacity, or FVC) and how quickly you do so (called forced expiratory volume or FEV). If your airways are swollen or constricted as a result of asthma or other lung diseases, your score will be lower. Your doctor may recommend several spirometry lung function tests to track your asthma’s progress over time. Spirometry may be performed before and after you take medication to determine whether the medication is effective. Additionally, your doctor may request readings during exercise to assess how your airways respond to exercise.
  • Challenge tests are lung function tests used to assist in the confirmation of an asthma diagnosis. You inhale a trace amount of a substance known to elicit asthmatic symptoms in some people, such as histamine or methacholine. Someone will examine your lung function after you have inhaled the substance. Since challenge tests can set off an asthma attack, you should only get them done by someone who knows what they’re doing.
  • Peak flow meter tests determine how well the lungs force air out. These lung function tests, though less precise than spirometry, can be a good way to assess your lung function at home on a regular basis — even before you have any symptoms. A peak flow metre will tell you what triggers your asthma, if your medication is effective, and when you should seek emergency assistance. The peak flow metre is a small plastic tube with a mouthpiece on one end from which you can breathe. Your doctor can request that you use the peak flow metre every day and record the results. You notify your doctor of the findings after a few weeks.
  • Exhaled nitric oxide test. You’ll breathe into a tube that’ll be connected to a system that’ll test how much nitric oxide is in your breath. This gas is usually produced by your body, but if your airways are inflamed, levels can be elevated.

Other Tests 


Your doctor can order additional tests to determine what is causing your asthma symptoms, even if your lung function tests are normal.

  • Gas and diffusion tests can determine how well oxygen and other gases in the air you breathe are absorbed by your blood. You inhale a small amount of gas, hold your breath, and then exhale. The amount of gas you exhale is measured in order to determine how much your blood has consumed.
  • X-rays may reveal whether you have any other lungs issues or whether your symptoms are due to asthma. A picture of your lungs is created by high-energy radiation. When standing in front of the X-ray machine, you will be asked to hold your breath for a short period of time.



Asthma can be more difficult to treat and manage if you have nasal polyps or sinusitis. Sinusitis, also known as a sinus infection, is an infection-related inflammation or swelling of the sinuses. Bacteria develop in the sinuses as they become blocked and filled with fluid, causing infection and inflammation. If your doctor suspects you have a sinus infection, he or she can schedule a CT scan to examine your sinuses. Antibiotics can be prescribed for at least 10 to 12 days if you have sinusitis. Sinusitis treatment can help prevent asthma symptoms.

Tests for Other Conditions


The doctor can also conduct tests to rule out other conditions that aggravate asthma, such as:

  • Gastroesophageal reflux disease (GERD)
  • Allergies

Severity of Asthma


Your doctor can diagnose you with asthma based on these tests and your symptoms. The next move is to determine the severity of your asthma. This will aid them in determining your course of treatment. One of these four forms of asthma can affect you:

  1. Mild intermittent asthma. Mild symptoms occur only once or twice a week. Symptoms at night occur less than twice a month. There are very few asthma attacks.
  2. Mild persistent asthma. Three to six days a week, you’ll experience symptoms. Three or four times a month, you’ll experience nighttime symptoms. Asthma attacks may make it difficult to do things.
  3. Moderate persistent asthma. Symptoms occur on a daily basis. Five or more days a month, you’ll experience nighttime symptoms. Asthma attacks have a negative impact on your daily activities.
  4. Severe persistent asthma. Symptoms are present at all times of the day and night. You have to restrict your tasks because they happen too often.

If you have asthma, your doctor will prescribe medicines to help you control your condition and avoid attacks.

Asthma Medications

Asthma medication is important in controlling your condition. There are two major treatment categories, each aimed at a certain objective.

  • Controller medications are the most effective drugs that avoid asthma attacks. Your airways are less inflamed and less likely to respond to triggers when you take these medications.
  • Quick-relief medications, also known as rescue medications, loosen up that surround your airway. If you need to take a rescue medication more than twice a week, your asthma isn’t under control. Some people with exercise-induced asthma use a rapid-acting beta-agonist prior to a workout.

With the right medication, you should be able to live an active and normal life. If your asthma symptoms remain uncontrolled, you should seek another form of treatment.

Long-Term Control Medications

Some of these medications should be taken on a daily basis to keep your asthma under control. Others are taken as needed to lessen the severity of an asthma attack. The most effective are those that reduce airway inflammation. Your doctor may advise you to combine an inhaled corticosteroid, an anti-inflammatory medication, and other medications such as 

  • Long-acting beta-agonists. A beta-agonist is a type of drug known as bronchodilator that opens your airways.
  • Long-acting anticholinergics. Anticholinergics ease breathing by relaxing and enlarging (dilating) the lungs’ airways (bronchodilators).
    • Tiotropium bromide (Spiriva Respimat) is an anticholinergic that is available to people aged 6 and up. This medication should be taken in conjunction with your routine maintenance medication.
  • Leukotriene modifiers inhibit the production of chemicals that cause inflammation.
  • Mast cell stabilisers prevent the release of inflammatory chemicals.
  • Theophylline is a bronchodilator that is used as a supplement for symptoms that do not respond to other medications.
    • Reslizumab (Cinqair) is an immunomodulator maintenance medication. It is taken in addition to your regular asthma medications. This medication is administered intravenously every four weeks over the course of about an hour. This medication works by reducing the number of eosinophils, which are white blood cells that play a role in the development of asthma symptoms. It has the potential to reduce severe asthma attacks.
    • Mepolizumab (Nucala) reduces blood eosinophil levels. It is prescribed as a maintenance therapy medication in the form of an injection every four weeks.
    • Omalizumab (Xolair) is an asthma maintenance medication that is an antibody that blocks immunoglobulin E (IgE). This keeps an allergen from causing an asthma attack. This medication is given via injection. To be eligible for this medication, a person must have an elevated IgE level as well as known allergies. Allergies must be confirmed through a blood or skin test.An immunomodulator is an injection given if you have moderate to severe asthma caused by allergies or other immune-related inflammation that does not respond to certain medications.

Quick-Relief Asthma Drugs

These medications provide rapid relief from the symptoms of an asthma attack, such as coughing, chest tightness, and wheezing. They include the following:

  • Short-acting beta-agonists (bronchodilators)
  • Anticholinergics. These are bronchodilators that can be paired with, or used instead of, short-acting beta-agonists.
  • Systemic corticosteroids are anti-inflammatory drugs that get symptoms under control.

Inhalers, Nebulizers and Pills 

Asthma medications can be taken in a variety of ways. Certain medications are inhaled with the aid of a metered dose inhaler, dry powder inhaler, or nebulizer (which changes medication from a liquid to a mist). Others are taken orally, either as pills or as a liquid. Additionally, they can be given via injection.

Certain asthma medications can be combined. In fact, some inhalers combine two medicines to get the drugs to the airways faster.

Over-the-Counter Asthma Treatments

The use of over-the-counter asthma drugs is usually discouraged. You should discuss the asthma symptoms with a doctor and follow their medical recommendations. OTC drugs are not long-term treatments and should not be used to manage your asthma on a regular basis. They should be avoided by people with high blood pressure, diabetes, thyroid disease, or heart disease.

Allergy Shots and Asthma

Latest findings indicate that children who receive allergy shots are less likely to develop asthma, although there are asthma shots specifically for teenagers and adults. Given that allergies are a known asthma trigger, it makes sense that controlling them will result in fewer asthma attacks.

Consult with your doctor to determine whether allergy shots are right for you.

Asthma Medication Frequency

Asthma is incurable. How often you have to take your medications depends on the severity and frequency of your condition. For instance, if you have difficulty only when you exercise, you may only need to use an inhaler prior to exercising. However, the majority of people with asthma require daily treatment.

Asthma Medication Guidelines

The key to effective asthma control is your medication treatment plan. Find out everything you can about them. Understand which treatments are included in your asthma action plan, when they should be taken, the expected outcomes, and what to do if the desired outcomes do not occur.

Remember to keep these general guidelines in mind as well.

  • Never run out of medication for asthma. At least 48 hours before you run out, call your pharmacy or doctor’s office. To make it easier to call for refills, save your pharmacy contact number, prescription numbers, and medication names and doses in your phone.
  • Make sure that you are aware of and capable of following your asthma care plan.
  • Before taking asthma medications, wash your hands.
  • Please take your time. Before you use any drug, double-check the name and dose.
  • Asthma medications should be stored according to the manufacturer’s instructions.
  • Check liquid drugs on a regular basis. If they’ve turned a different colour or shaped crystals, throw them out and replace them.
  • Any other drugs you’re taking should be disclosed to your doctor. When you take those medications together, they don’t function as well. While the majority of asthma drugs are safe, some do have side effects. Request a description from your doctor or pharmacist, and report something odd or serious.


Referenced on 11/4/2021

  1. The Canadian Lung Association: “Signs and Symptoms of Asthma: Diagnosis."
  2. National Jewish Medical and Research Center: “How Is Asthma Diagnosed?"
  3. American College of Allergy, Asthma & Immunology: “About Asthma: Diagnosing Asthma."
  4. Mayo Clinic: “Asthma: Steps in testing and diagnosis.”
  5. Medscape: “Asthma Guidelines.”
  6. American Academy of Asthma, Allergy, and Immunology: “What to expect at the doctor’s office."
  7. American Lung Association: “Spirometry and Other Lung Function Tests Fact Sheet."
  8. American Medical Association: Essential Guide to Asthma.
  9. Asthma and Allergy Foundation of America: “Peak Flow Meters."
  10. Grayson, M. ACP Medicine, 2005.
  11. National Asthma Education and Prevention Program: “Expert Panel Report 3: Guidelines for the Diagnosis and Management of Asthma — 2002."
  12. National Heart, Lung and Blood Institute: “Asthma: How is Asthma Diagnosed?"
  13. MedlinePlus: “Pulmonary Function Tests."
  14. National Lung Health Education Program: “Spirometry."
  17. American Academy of Allergy Asthma & Immunology: “AAAAI Allergy & Asthma Medication Guide." 
  18. American Academy of Family Physicians: Family Doctor: “Asthma: Learning to Control Your Symptoms." 
  19. American Lung Association: “Asthma Medicines."
  20. FDA News Release. “FDA approves Cinqair to treat severe asthma.”
  21. Medline Plus: “Asthma." 
  22. Boehringer Ingelheim: “US FDA Expands Approval of Tiotropium Respimat® for Maintenance Treatment of Asthma in Children."
  23. FDA. Prescribing Information: Spiriva Respimat.

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