Should CF Patients Do Extra Airway Clearance on Smoky Days?

While there are no universal medical guidelines that require all people with cystic fibrosis (CF) to increase airway clearance therapy (ACT) simply because it is a smoky day, many patients may need to do extra sessions if they develop respiratory symptoms ^[1][2]. Wildfire smoke and poor air quality are known to irritate the lungs and increase mucus production. Because people with CF already have impaired mucociliary clearance (the lung’s natural ability to sweep away mucus and trapped particles), they are especially vulnerable to environmental triggers ^[3]. If you experience increased coughing, shortness of breath, or chest tightness, you should follow your personal “sick day” plan, which often includes stepping up your airway clearance and contacting your CF care team ^[4][5].

Why Smoke is Dangerous for CF Lungs

People with CF are particularly vulnerable to the harmful effects of air pollution ^[3]. Wildfire smoke contains fine particulate matter (often referred to as PM2.5), which are tiny particles that can travel deep into the lungs. Research has established that exposure to poor air quality and fine particulate matter is a significant risk factor for a decline in lung function and an increase in pulmonary complications in people with CF ^[1][6][7]. In young children specifically, air pollution can even increase the risk of initially acquiring harmful lung bacteria, such as MRSA ^[8].

Because your lungs already have difficulty clearing thick, sticky mucus, the added burden of inhaling smoke particles can overwhelm your airways ^[3]. The body’s natural response to this irritation is often to produce more mucus, making effective clearance even more critical.

Managing Your Routine During High-Pollution Events

Currently, medical literature does not outline a specific, standardized protocol for adapting airway clearance techniques or nebulized medications universally for all CF patients during high-smoke events ^[1][2]. Instead, care must be tailored to your specific needs. Airway clearance therapy is a cornerstone of CF management, and clinicians are encouraged to adapt therapy to changing patient needs ^[4][5].

Here is what you should consider when air quality drops:

• Monitor Your Symptoms: Pay close attention to your body. If you notice an uptick in coughing, chest congestion, or a change in the color or volume of your mucus, this is a signal that your lungs are struggling with the air quality.
• Activate Your Action Plan: Many CF care centers provide a sick day or exacerbation (a sudden worsening or flare-up of your lung symptoms) action plan. If smoke triggers respiratory symptoms, your doctor may recommend treating it similarly to a mild exacerbation. This often involves increasing the frequency or duration of your ACT sessions ^[4][5].
• Focus on Prevention: The most effective strategy is reducing your exposure to poor air quality ^[2]. Stay indoors with windows and doors closed, use high-quality HEPA air purifiers if possible, and avoid outdoor activities when the Air Quality Index (AQI) reaches “Unhealthy for Sensitive Groups” (typically above 100). If you must go outside, wearing a well-fitted N95 or KN95 mask can help filter out dangerous PM2.5 particles. Additionally, avoid creating indoor air pollution by avoiding burning candles, using strong chemicals, or smoking indoors, as this trapped air will further irritate your lungs.
• Consult Your Care Team: Because nebulized therapies like dornase alfa and hypertonic saline (medications that thin out mucus) are crucial for improving mucociliary clearance in CF patients ^[9][10], your care team should guide any changes to your medication dosing or ACT schedule based on your specific baseline lung function and current symptoms.