Some factors that contribute to bronchospasm include consuming certain foods, taking certain medicines, allergic responses to insects, and fluctuating hormone levels, particularly in women.

During general anesthesia, signs of bronchospasm include wheezing, high peak inspiratory pressures, increased intrinsic PEEP, decreased expiratory tidal volumes, and an upsloping capnograph (obstructive pattern).

Lower respiratory tract conditions such as asthma, chronic obstructive pulmonary disease (COPD), and emphysema can result in contraction of the airways.

Beta blockers bind to the β2 receptors and block the action of epinephrine and norepinephrine causing shortness of breath.

The neurotransmitter acetylcholine is known to decrease sympathetic response by slowing the heart rate and constricting the smooth muscle tissue.