When Asthma Isn’t Asthma: The Hidden Risks of Misdiagnosis and Wrong Treatment

Kate Baumwol brings over 20 years of experience as an advance practice Speech Pathologist, specialising in voice, chronic cough, inducible laryngeal obstruction (ILO), and exercise-induced laryngeal obstruction (EILO). She currently coordinates the Joint Speech Pathology Airway Clinic and Voice Clinic at Sir Charles Gairdner Hospital and operates private clinics at the Perth ENT Centre.

Dr Alice Crawford is a consultant respiratory physician with expertise in asthma and related conditions. At Sir Charles Gairdner Hospital, Dr Crawford works in the Airways team assessing suitability for severe asthma biologics and advanced therapies, and also leads an undifferentiated breathlessness multidisciplinary clinic.

Asthma is one of Australia’s most common chronic health conditions — but not every wheeze, cough, or episode of breathlessness is asthma. Every year, thousands of Australians are misdiagnosed and placed on the wrong treatment. In some cases, this can worsen health outcomes, as asthma medications may aggravate non-asthma conditions.

A common example is Inducible Laryngeal Obstruction (ILO). Its symptoms — breathlessness, chronic coughing, throat tightness, and voice changes can look similar to asthma. But the underlying cause and the treatment required are completely different. Recognising these differences is critical to ensuring patients get the right care at the right time.

International studies reveal the extent of misdiagnosis: up to 35% of adults and 48% of children with an asthma label may not actually have it. A large Canadian study published in JAMA found that one in three adults told they had asthma showed no evidence of the disease when objectively tested — trends that are increasingly recognised in Australia. 

Respiratory specialists frequently see patients labelled with “asthma” who are later diagnosed with conditions such as ILO, where the voice box narrows abnormally during breathing. In these cases, the problem isn’t failed asthma treatment — it is that the real condition has gone unrecognised. The consequences are significant: ongoing symptoms, repeated flare-ups, unnecessary healthcare costs, and even patients losing confidence in their GP. Long-term use of asthma medicines without a correct diagnosis also carries risks, including corticosteroid side effects and dangerous overuse of reliever inhalers.

Asthma is often diagnosed based on symptoms alone, without objective tests such as spirometry, FeNO, or bronchial challenge which can confirm or rule out the condition. Barriers include limited access to testing, uncertainty in interpreting results, or patients simply carrying forward an old diagnosis that has never been reviewed. When asthma is assumed rather than confirmed, patients may endure years of ineffective treatment, side effects, and repeated flare-ups — while the real condition remains untreated.

Signs to watch out for that suggest symptoms may not be asthma: 

• Sudden onset breathlessness triggered by activity or irritants 
• Rapid resolution once the trigger passes 
• Persistent throat irritation or voice changes 
• Little or no improvement despite standard asthma treatment

This diagram has been included with consent from the authors.

Asthma medications are not without side effects. Inhaled corticosteroids can cause oral thrush, hoarseness, a sore throat and increase the risk of infections. While reliever inhalers (SABAs) may trigger a racing heart, tremors, or anxiety. More concerning is the routine prescription of short courses of oral corticosteroids for presumed asthma exacerbations, which can result in harmful cumulative effects. Misdiagnosis can delay effective care, leaving patients trapped in a cycle of symptoms and unnecessary treatments.

For ILO, the best results come from non-medication therapies.

• Speech pathology can teach patients specialised breathing techniques and strategies to improve laryngeal control during breathing, promoting normal airway function, and preventing ILO episodes.
• Biofeedback can give patients real-time insight into their breathing, helping them adopt calmer, more efficient patterns that reduce the frequency and severity of episodes.

These strategies empower patients to manage symptoms, reduce reliance on medication, and regain confidence and quality of life.

If asthma treatment isn’t helping, it’s important to ask questions: “Am I on the correct treatment?”, “Could something else be causing my breathing problems?” or “Can I have tests to confirm this is really asthma?” Revisiting the diagnosis can be life-changing, helping patients and families play an active role in getting the right care.

Jane* (48) spent years struggling with coughing fits, shortness of breath, and noisy breathing. Diagnosed with asthma by her GP, she was prescribed multiple inhalers, frequent courses of oral steroids and antibiotics, and was even hospitalised for what was believed to be an asthma exacerbation. Despite escalating treatment, her lung function remained normal — but her symptoms persisted. 

Over time, the overuse of asthma medications took a significant toll: Jane developed oral  and laryngeal thrush, gained weight, and suffered from severe sleep disruption. These led her to fear she had “difficult-to-treat asthma”, reinforcing her dependence on medication and prompting multiple emergency department presentations when her symptoms felt unmanageable. This ongoing cycle of ineffective treatment and uncertainty deeply impacted her quality of life and mental health.

After referral to the joint Speech Pathology Airway Clinic, Jane was diagnosed with ILO. Through breathing retraining, cough suppression techniques, and education, she regained control of her symptoms. Today, Jane is living well and medication-free, equipped with strategies to prevent relapse. Her story highlights the critical role of accurate diagnosis and the value of speech pathology in breathing disorders.

Not every cough, wheeze, or breathless episode is asthma. Misdiagnosis can cost years of ineffective treatment, side effects, and uncertainty. Jane’s story shows that with the right assessment and targeted therapy, patients can regain control, live medication-free, and breathe easier — both physically and mentally. Asking questions, seeking tests, and exploring alternative diagnoses can make all the difference in finding the right care at the right time.