nebulizer

A nebulizer turns a liquid drug solution into a continuous fine mist that the patient simply breathes in through a mask or mouthpiece over several minutes, breathing normally. Instead of one quick puff, it is more like sitting in a gentle medicated fog until the dose is delivered.

Two common types create the mist. A jet (pneumatic) nebulizer blows compressed air or oxygen through a narrow nozzle over the liquid, shearing it into droplets and letting only the small ones escape while larger drops fall back. An ultrasonic nebulizer uses a vibrating piezoelectric crystal to shake droplets off the liquid surface; newer vibrating-mesh nebulizers push liquid through thousands of tiny holes. Each produces an aerosol whose droplet size — ideally a few micrometres — determines how deep into the lung it deposits.

Nebulizers shine when a patient cannot use an inhaler properly: infants, the very elderly, or someone in acute respiratory distress, because they need only passive tidal breathing and no coordination. The trade-offs are that they are bulkier, need a power or air source, take longer (often 5–15 minutes), and can waste drug during exhalation. Heat-sensitive drugs (such as some proteins) may also be degraded by ultrasonic devices, so device choice depends on the drug.