If someone complains of wheezing, the healthcare provider will need more information. Sometimes a healthcare provider will detect wheezing during a physical exam when the person doesn't even notice it. This usually occurs after exposure to certain triggers, such as pollen, cold air, or exercise. This commonly occurs in young children who can accidentally inhale small objects they put into their mouths. Sometimes no cause can be found.
Prevention is related to the cause.
For instance, avoiding smoking can prevent most cases due to emphysema or lung cancer. Keeping small objects away from young children can prevent some cases due to a foreign body. Many cases cannot be prevented. The first step in figuring out the cause is a history and physical exam. This may be all that is needed to make the diagnosis.