A pressurized metered-dose inhaler, or pMDI, serves as a common device for delivering medication directly into the lungs. It is used to manage various respiratory conditions, providing targeted relief for breathing difficulties by ensuring medication reaches the airways.
Understanding Your pMDI Inhaler
A pMDI inhaler consists of a metal canister that holds the medication, a plastic actuator, and a mouthpiece. The canister contains medication suspended in a propellant, a gas that helps aerosolize the drug. When the canister is pressed into the actuator, a precisely measured dose of medication is released.
This medication is then expelled as a fine mist through the mouthpiece. Propellants, such as hydrofluoroalkanes (HFAs), create the pressurized spray. This design ensures a consistent, controlled dose with each actuation.
Correct Usage Techniques
Properly using a pMDI inhaler begins with preparing the device. Before first use, or if unused for several days, “prime” the inhaler by releasing a few test sprays into the air away from the face. This ensures a full dose of medication is delivered. Shaking the inhaler vigorously for 5-10 seconds before each use also helps mix the medication evenly with the propellant.
Next, focus on your breathing pattern. After exhaling fully, place the mouthpiece in your mouth, creating a tight seal around it. As you begin to slowly and deeply inhale through your mouth, simultaneously press down on the canister to release a puff of medication. This coordination is important for the medication to travel effectively into the lungs.
After inhaling the medication, it is beneficial to hold your breath for approximately 5 to 10 seconds. This pause allows medication particles to settle deeply within the airways. If more than one puff is prescribed, waiting 30 to 60 seconds between puffs allows airways to open slightly, potentially improving subsequent dose delivery. A spacer device, a hollow chamber attached to the inhaler, can simplify coordination and improve medication delivery by holding the mist until it can be inhaled.
Ensuring Effectiveness and Troubleshooting
Effective medication delivery from a pMDI inhaler relies on correct execution. When technique is not followed precisely, such as not shaking the inhaler or failing to coordinate the breath with the spray, medication may not reach the lower airways. This can lead to less effective symptom management, as medication may deposit in the mouth or throat instead of the lungs.
Signs that an inhaler might not be performing as expected include a lack of spray, no sensation of medication entering the mouth or throat, or worsening respiratory symptoms despite regular use. These issues often stem from common user errors. For instance, breathing in too quickly or not holding the breath can reduce the amount of medication that reaches the lungs.
If the inhaler produces no spray, check if it is empty; many inhalers have dose counters. If medication remains, a blockage in the mouthpiece or actuator might be present, which cleaning can resolve. Addressing these technique errors or device issues helps ensure the medication provides its intended therapeutic effect.
Maintenance and Storage
Regular cleaning of the pMDI inhaler is important to prevent blockages and maintain hygiene. The plastic actuator and mouthpiece should be cleaned at least once a week. This involves removing the metal canister and rinsing the plastic components under warm running water for about 30 seconds. After rinsing, the parts should be allowed to air dry completely before reassembling the inhaler.
Proper storage conditions contribute to the inhaler’s longevity and medication stability. Inhalers should be stored at room temperature, between 59°F and 77°F (15°C and 25°C), away from direct sunlight and extreme temperatures. Exposure to excessive heat or cold can affect the medication’s integrity or the propellant’s effectiveness. Many inhalers include a dose counter to indicate the remaining number of sprays, providing a clear signal for when a replacement is needed.