If possible, see a functional medicine doc or legit qualified naturopathic doc. there are different underlying causes of asthma, and addressing it from the cause can help reduce episodes and lessen need for suppressive therapies. But asthma is serious and your friend must keep inhaler/nebulizer treatments on hand and avoid triggering it.

FWIW, I developed reactive-airway-syndrome and was taking Advair; my naturopath gave me this which helped me replace the Advair. But your friend may need another approach, particularly if the asthma is related to allergies and/or food sensitivities. It’s not one size fits all, but there is definitely hope and more options than just relying on inhalers.