Asthma is no longer considered an absolute barrier to scuba diving.
While serious problems can arise in patients with asthma who dive, they are exceedingly rare except in people with severe or uncontrolled asthma. Most experts – both medical societies and diving groups – now agree that patients with asthma can safely dive if their asthma is not severe and is well controlled. If you have asthma and would like to dive, we’ll do everything we can to enable you to participate in the fun of scuba diving safely!
Lung function testing is performed, and an individualized treatment plan is formulated to maximize lung function and minimize lung inflammation. We also need to repeat the lung function testing once treatment has been maximized, to make sure that it is effective at making overall lung function nearly normal. There is concern that if the inflammation of asthma has resulted in scar tissue formation, this could lead to problems during ascent at the end of a dive. Although there is no way to know with certainty if scar tissue has developed or if it would lead to any problems, it is generally accepted that the likelihood of complications is very low if we can show that lung function can be made almost completely normal with treatment.
An exercise challenge is performed to ensure that lung function does not decrease with physical activity. The concern is that if strong currents are encountered at depth that makes the dive physically more strenuous, we need to know that swimming hard against the current won’t cause an exercise-induced asthma attack.
Another element of a full evaluation that may or may not be required is to make sure that fine salt water spray does not induce an asthma exacerbation. This is not common, so it depends on a given patient’s history as to whether this evaluation would be recommended.