Last reviewed 2026-04-23 · How we verify

Inhaled mannitol

Inhaled mannitol acts as an osmotic agent that draws fluid into the airways to hydrate secretions and improve mucociliary clearance.

Inhaled mannitol acts as an osmotic agent that draws fluid into the airways to hydrate secretions and improve mucociliary clearance. Used for Cystic fibrosis, Bronchiectasis.

At a glance

Mechanism of action

Mannitol is a sugar alcohol that, when inhaled as a dry powder, creates an osmotic gradient in the airway lumen. This draws water into the airway surface liquid, hydrating thick mucus and improving its clearance by cilia. The mechanism is thought to reduce airway inflammation and improve lung function in conditions characterized by dehydrated secretions.

Approved indications

• Cystic fibrosis
• Bronchiectasis

Common side effects

• Cough
• Throat irritation
• Bronchospasm
• Wheezing

Key clinical trials

• Open-label Study to Assess Reduction of Background Asthma Medication While Sustaining Asthma Control and Clinical Remission With Tezepelumab in Patients 12-80yrs With Severe Asthma. (PHASE3)
• PT027 Compared to PT007 in Patients With Asthma With Mannitol-induced Acute Airway Obstruction (PHASE3)
• Inhaled Mannitol on Mucociliary Clearance in Moderate to Severe Cystic Fibrosis (PHASE4)
• Development of an Interactive Digital Respiratory Game and Device and Investigation of Its Effectiveness in Children With Bronchiectasis (NA)
• National Cohort of Subjects at Risk of Developing Rheumatoid Arthritis
• Sensory-Mechanical Responses to Eucapneic Voluntary Hyperventilation and Mannitol (PHASE4)
• Reference Ranges for the Cough Responsiveness to Inhaled Mannitol (NA)
• U-LABA/ICS Effects on Exercise Performance, Formoterol (NA)

Primary sources

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