What causes bronchial spasms?
Bronchial spasms are caused by the release of substances from mast cells or basophils under the influence of anaphylatoxins.
Bronchial spasms occur when bronchial tubes become inflamed due to lower respiratory tract conditions such as asthma, chronic obstructive pulmonary disease and emphysema.
Side effects of topical decongestants such as oxymetazoline and phenylephrine may also cause bronchial spasms. Non-selective beta blockers bind to beta2 receptors and block the action of epinephrine and norepinephrine from binding to its receptors, causing shortness of breath.