What Are the Components of an Inhaler?

Asthma is a disease affecting the lungs that can cause symptoms of chest tightening, coughing, wheezing and breathlessness. According to the Centers for Disease Control and Prevention, 7.7 percent of U.S. adults and 9.6 percent of U.S. children have asthma. Medication is available for people who suffer from asthma and is usually administered through an inhaler. If you or your child suffer from asthma, knowing the components of an inhaler may be helpful information before visiting your doctor for more health advice.

Types of Inhalers

• An inhaler is a hand-held plastic tube that holds the asthma medicine and directs it quickly to the lungs. Although asthma medication may be delivered orally or intravenously, using an inhaler is the most effective way to administer asthma medication directly to the lungs. In addition, some asthma medications can only be inhaled. There are two main types of inhalers: metered dose inhaler (MDI) and dry powder inhaler (DPI).

Metered Dose Inhaler

• The MDI consists of two main parts: a metal canister containing the medicine and a plastic tube with a mouthpiece at the bottom. The canister fits into the top part of the tube. Pressing on the canister opens a valve at its base and a jet of air and medicine (a metered dose) is dispensed into the tube and then forced into the airways. Sometimes the MDI is equipped with an add-on device called a chamber or spacer. This is usually used on children, but can be used on adults as well. It is a tube with one end attached to the mouthpiece and the other end over the child's face. The spacer helps reduce the speed of medication entering the lungs to ensure that the medicine actually gets into the lungs rather than the mouth.

Dry Powder Inhaler

• The DPI is usually packaged in single dosages as blisters or gel capsules. It can be shaped as a tube or a disk. Generally, it is a single tube-like structure consisting of a shaft and a base (or a disk with a mouthpiece). The base (or disk) twists. A single twist allows a single dose of medicine to be loaded. The shaft is inserted into the mouth and the medication is inhaled. To use this type of inhaler the person must inhale the powdered medicine quickly and forcefully. This type of inhaler may be challenging for a child or for anyone suffering from an asthma attack as it may be difficult to inhale deeply.

Counter

• Some manufacturers have added a counter to the inhaler mouthpiece so the number of uses can be recorded and tracked. Some inhalers are sold as one unit; others are designed to refill the canisters separately.