What causes frequent asthma?

Lots of things. There are many asthma triggers. In some cases they can be identified & avoided, or desensitization therapy by an allergist might help. But in most cases, the triggers are difficult if not impossible to avoid, and the answer lies in calming down the asthma response with an inhaled corticosteroid. If asthma symptoms are frequent or severe, increased treatment is needed to avoid serious consequences.
Asthma. Frequent bouts of asthma are caused by exposure to various allergens like dust, molds, or dust mites. This time of year the pollens such as trees, grass and weeds can be a problem.