A growing body of evidence suggests there are different kinds of asthma that may require different approaches, The Wall Street Journal reports.

Every day millions of asthma patients follow the standard doctor-recommended treatment: They take puffs from their steroid inhalers. Amber Keating is one of them. For 19 years, a daily steroid inhaler has been a cornerstone of the 42-year-old Los Angeles resident’s treatment. But in recent years she began to question its effectiveness as she had more flare-ups.