An inhaler is a small, handheld device designed to deliver medication directly into the lungs through the airways. This method is highly effective because it targets the site of inflammation or bronchoconstriction, allowing for a rapid and concentrated therapeutic effect. Proper technique is crucial, as errors can significantly reduce the amount of medication reaching the lungs, often leaving most of the dose deposited in the mouth and throat. All inhaler types require specific, learned steps to ensure the prescribed medication works as intended.
Step-by-Step Guide for Metered-Dose Inhalers
The Metered-Dose Inhaler (MDI) delivers medication as a fine, aerosolized mist propelled by a chemical. Before use, check the dose counter to confirm medication remains. The inhaler must be shaken vigorously for five seconds to ensure the drug and propellant are properly mixed for uniform dose delivery. New inhalers, or those unused for a week or more, require priming by releasing a few test sprays away from the face.
To prepare, remove the cap and hold the inhaler upright with the mouthpiece at the bottom. Exhale slowly and completely to empty the lungs. Place the mouthpiece into the mouth, sealing the lips tightly around it. Proper coordination is required: begin a slow, deep breath in through the mouth while simultaneously pressing down on the canister once to release the medicine.
The inhalation must be slow and steady to allow the mist to travel deep into the lower airways, rather than impacting the back of the throat. After the puff is released, remove the inhaler from the mouth. Hold the breath for five to ten seconds, or as long as comfortably possible, to allow the drug particles to settle in the lungs. If a second puff is required, wait about one minute before shaking the inhaler and repeating the entire sequence.
When and How to Use a Spacer Device
A spacer, or valved holding chamber, is a tube that attaches to the MDI mouthpiece. This device is recommended for most MDI users because it holds the aerosolized medication after actuation, eliminating the need for precise hand-breath coordination. By capturing the medication, the spacer allows the user to inhale the dose at their own pace, significantly reducing deposition in the mouth and throat.
To use the MDI with a spacer, shake the inhaler and attach it to the spacer’s opening. Exhale fully, place the spacer mouthpiece in the mouth, and create a tight seal. Press the canister once to release a puff into the chamber, then immediately begin to breathe in slowly and deeply through the mouthpiece.
Slow inhalation is important; breathing too quickly may cause a whistling sound in some models, indicating the breath is too fast for optimal delivery. After inhaling the dose, hold the breath for up to ten seconds to maximize lung deposition. For individuals who cannot hold their breath, such as young children, the technique involves breathing in and out normally through the spacer for five to ten breaths after the puff is released.
Technique for Dry Powder Inhalers
Dry Powder Inhalers (DPIs) do not use a propellant, unlike MDIs. The drug is in a fine powder form and is breath-activated, requiring the user’s inspiratory force to draw the dose into the lungs. DPIs cannot be used with a spacer, and the technique requires a rapid, strong inhalation to break up the powder and carry it effectively.
First, prepare the inhaler by loading the dose, often by sliding a lever or twisting the device until a click is heard. Do not breathe into the DPI, as moisture from the breath can cause the powder to clump and prevent proper inhalation. Exhale fully away from the device before placing the mouthpiece in the mouth.
The inhalation must be a quick, forceful, and deep breath taken through the mouth, often described as sucking a milkshake. This fast, high-flow rate creates the turbulence necessary to disperse the powder into fine, respirable particles. After the rapid inhalation, remove the device and hold the breath for five to ten seconds to allow the particles to settle.
Maintenance and Replacement Guidelines
Proper maintenance ensures the inhaler remains clean and functional. For MDIs, remove the metal canister and clean only the plastic mouthpiece and cap, typically once a week. Rinse these plastic parts under warm running water and allow them to air-dry completely overnight, as moisture interferes with drug delivery. The metal canister must never be submerged in water.
DPIs must be kept dry at all times and should never be cleaned with water. Wipe the DPI mouthpiece regularly with a clean, dry cloth to remove residue. Store both types of inhalers at room temperature, away from excessive heat, cold, or direct moisture, to protect the medication’s integrity.
Most modern devices have a dose counter indicating the number of doses remaining. Replace the inhaler when the counter reaches zero, even if some spray is still emitted, as the medicine is no longer delivered at the correct dose. If an MDI lacks a counter, users must track the number of puffs used to ensure timely replacement.