hello common breathing problems include chronic sinusitis , allergies and asthma now as you tell that one capsule in the pump makes your husband relax so i presume that he must be using something like asthalin so what i would suggest is that you apy a visit to your chest specialist who will perform some tests like physical examination ,pulmonary function test ,spirometry a metacholine challange test may be performed to help a diagnosis of athma if its asthma than you can try avoiding asthma trigger factors like viral infection pet dander pollen mold spores smoke food allergies dust mites fumes/polluted air etc even exercise may be a trigger in some persons now an accurate diagnosis is important before you can treat and prevent breathing problems as each individual is different and may have different triggers so do visit a chest specialist to get it sorted out best of luck