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What Causes Asthma in Adults?

Thursday 16 May 2024
6 minute(s) read

Table of Contents

I. What Causes Adult-Onset Asthma?

II. Asthma Symptoms in Adults

III. Asthma in Children vs. Asthma in Adults

IV. Asthma Treatment

i. Medications

ii. Avoiding Triggers

V. Conclusion

Many adults are surprised to experience asthma symptoms for the first time later in life. But asthma can arise at any age, even if you've never had breathing problems before. [1]

The good news is that asthma is a manageable condition. With proper treatment and lifestyle adjustments, most people with asthma can keep their symptoms under control and live active, healthy lives. In this article, we'll look at the causes of adult-onset asthma, how it differs from asthma in children, and the common symptoms of asthma in adults. 

What Causes Adult-Onset Asthma?

Adult-onset asthma develops after the age of 20 and can be triggered by various factors. For some, exposure to certain allergens or irritants for the first time as an adult can bring on symptoms. For others, a viral infection may unmask underlying asthma. In some cases, childhood asthma that appeared to resolve can come back during adulthood. [1]

While the exact cause of asthma is unknown, [1] there are several potential causes for asthma beginning in adulthood.

  • Resurgence of childhood asthma: Asthma is a chronic condition, so even if symptoms improve or disappear in childhood, airway inflammation may persist. Studies show childhood asthma often recurs in the 30s and 40s. Regardless of asthma activity, avoid triggers and keep rescue inhalers up to date. [2]
  • Allergies: Around 30% of adult asthma is allergy-induced. Exposure to allergens like pet dander, mold, dust, or chemicals may trigger the initial onset of symptoms in adults. [3]
  • Occupational exposures: A common cause of adult asthma is workplace exposure to gases, fumes, and dust. [4]
  • Hormonal changes: Hormone fluctuations in women, such as during pregnancy or menopause, can play a role in adult-onset asthma. Some women first develop symptoms during or after pregnancy or during menopause. [3]
  • Obesity: Excess weight, especially around the chest, can make breathing more difficult and promote inflammation that worsens asthma. [4]

Asthma Symptoms in Adults

Symptoms of asthma in adults and children are the same. However, asthma symptoms in adults tend to be more persistent. [5]

Signs of asthma in adults include:

  • Shortness of breath: You may feel like you can't get enough air into your lungs. This can make it difficult to breathe and engage in normal activities.
  • Frequent coughing: Coughing, especially at night, is a hallmark sign of asthma in adults. The cough can be dry or produce mucus.
  • Wheezing: Wheezing causes a whistling sound during breathing due to inflammation and narrowing of the airways. 
  • Chest tightness: You may experience a feeling of heaviness, tightness, or pressure in the chest. This discomforting symptom can range from mild to severe during an asthma flare-up. [5]

These symptoms can appear gradually over time or suddenly during an asthma attack. If left unmanaged, asthma causes permanent changes in lung function. That's why long-term, consistent treatment of asthma is important. [4]

Asthma in Children vs. Asthma in Adults

a mother helping her son use an asthma inhaler

Asthma affects children and adults differently. While the core symptoms are often similar, there are some key differences between asthma in children and adult-onset asthma. [6]

  • Symptom duration: Asthma in children is often intermittent, with symptoms flaring up and easing over time. In many cases, children may outgrow their asthma symptoms upon reaching puberty. Asthma in adults, on the other hand, tends to be more persistent and long-lasting.
  • Types of symptoms: While children and adults share some of the common signs of asthma like wheezing, coughing, and chest tightness, children may exhibit some additional symptoms. These include flaring nostrils, tiredness, and poor appetite. Adults typically do not experience these types of symptoms. 
  • Gender disparity: Asthma tends to be more prevalent in male children compared to female children, affecting 8.4% of boys and 5.5% of girls. This trend reverses in adulthood, with asthma becoming more common in women.
  • Complications: Adults are five times more likely to die from asthma than children. Women also have a higher risk of dying from asthma compared to men.
  • Medication interactions: Certain heart medications like beta blockers, aspirin, and ACE inhibitors can potentially interact with asthma medicines or trigger asthma-like symptoms. Heart medication use in children is less common than in adults. [6]

Asthma Treatment

a woman using an asthma inhaler

Managing asthma requires a multi-pronged strategy. Medications can help control symptoms and improve lung function, but avoiding triggers is equally crucial. This combined approach is important in maintaining respiratory health.


Medications play a crucial role in managing asthma, and the type and frequency of medication you require will depend on the severity of your condition. There are two main categories of asthma medications: controllers and bronchodilators.

  • Controllers reduce inflammation in your airways. It is important to take these medications daily to maintain long-term control over your asthma. By consistently using controllers, you will notice a reduction in symptoms as the medication treats the underlying inflammation.
  • Bronchodilators provide relief from bronchoconstriction, which is the narrowing of the airways. They help relax and widen the airways, making it easier to breathe. Bronchodilators can be short-acting or long-acting. Short-acting bronchodilators are often referred to as "rescue" inhalers and are used for immediate short-term relief from sudden asthma symptoms. Long-acting bronchodilators take longer to provide relief but provide extended relief compared to rescue inhalers. [7]

If you require both controller and bronchodilator medications, your doctor may prescribe a combination inhaler for convenience. These inhalers contain both medications in one device. [7] Popular combination inhalers include:

Avoiding Triggers

If you have asthma, knowing your triggers and avoiding them is critical to managing your condition and preventing attacks. An asthma attack occurs when your symptoms worsen due to exposure to certain triggers. The triggers that lead to an asthma attack can differ from person to person. [8]

Some of the most common triggers include:

  • Second-hand smoke and tobacco smoke contain harmful chemicals that can irritate your lungs and airways, leading to an asthma attack. Do your best to avoid smoking and exposure to second-hand smoke.
  • Dust mites are tiny bugs that live in many homes. For those with dust mite allergies, exposure can trigger an asthma attack. Use allergen-proof covers for bedding, wash bedding weekly in hot water, reduce humidity, and avoid down bedding.
  • Outdoor air pollution from sources like vehicle emissions, wildfires, and factories releases gases and small particles that can trigger attacks. Monitor air quality forecasts and limit time outside when pollution levels are high.
  • Pet dander and saliva contain proteins that can trigger attacks in those with pet allergies. If possible, find a new home for pets. Otherwise, bathe pets weekly, keep them out of the bedroom, use an air purifier with a HEPA filter, and use allergen-proof bedding.
  • Mold growth releases spores that can trigger attacks even without an allergy. Excess moisture leads to mold in places like bathrooms, kitchens, basements, or areas with water damage. Eliminate excess moisture and clean up any mold to help prevent attacks.
  • Disinfectants and harsh cleaning products contain chemicals that can irritate your lungs and airways, triggering an attack. Stay away from areas where these products were recently used or are in use. [8]


Asthma is a condition that can develop at any stage of life, and it is crucial to remain vigilant for its symptoms. If you suspect that you may be experiencing signs of asthma, it is essential to seek medical attention. The good news is that there are numerous treatments and lifestyle adjustments that can help you effectively manage your asthma as an adult.

The content in this article is intended for informational purposes only. This website does not provide medical advice. In all circumstances, you should always seek the advice of your physician and/or other qualified health professionals(s) for drug, medical condition, or treatment advice. The content provided on this website is not a substitute for professional medical advice, diagnosis, or treatment.