Why Are So Many Asthma Medicines In Inhaler Form?

The inhaled route of medication delivery represents an ideal method of treating asthma. Asthma is a disease that involves the lungs and bronchial passageways. It therefore makes perfect sense to deliver the medicine directly where it is needed—right into the air passages. When inhaled correctly, asthma medication goes precisely where it is required, with minimal, if any, absorption by other organs.

By limiting the presence of medicine in the bloodstream and other organs, potential drug interactions are avoided and side effects and toxicity are minimized. There are two types of inhalers: metered-dose inhalers (MDIs) and dry-powder inhalers (DPIs). MDIs and DPIs are practical, portable, and fit in a schoolbag, pocket, or handbag. They work at room temperature and can be taken without regard to meals or time of day.

With proper instruction, motivated children as young as 5 or 6 years can learn to use inhaled asthma medications, via either an MDI or a DPI. The use of a spacer device such as a holding chamber (reviewed in more detail in Question 66) in combination with an MDI is recommended for all children (and for many adults too) in order to maximize the effectiveness of their MDIs.