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"Why does my asthma get worse in humid weather?"

ZocdocAnswersWhy does my asthma get worse in humid weather?


I am a 32-year-old woman living in the Midwest. I have allergic asthma, and my asthma tends to be worse in the fall. However, sometimes in the summer when it's really humid, I notice that I need to use my inhaler more frequently. I do not exercise outside and only walk at a moderate pace. Do you know what could be causing these flare-ups?


Most people with asthma have several allergic triggers which result in asthma flares. These allergic triggers are many, but include dust mites, cockroaches, mice, pollen, pet dander, and fungal spores. Whenever the concentration of of these agents is increased in the air that the asthmatic is breathing, this could trigger a flare. In your case, where you have specifically noted an association between humid weather and asthma flares, what is likely going on is that the humidity and wet air allows dust mites and fungi to proliferate, leading to higher concentrations of these contaminants in the air and causing a flair. To support this hypothesis is the observation that many asthmatics get better if they have air conditioning in their homes, presumably because the cooler, drier air inhibits dust mite proliferation. If these symptoms are particularly bothersome to you, you should talk to your primary care doctor or your allergist. This is because you may need to think about increasing your dose of or adding a maintenance medication during this period of the year. Maintenance medications have the advantage of preventing flares and keeping your symptoms under control without having to use your rescue inhaler or limit your physical activity as you currently are doing.

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