I would caution anyone, but especially people with compromised lungs, that inhaling anything not intended to be inhaled can be dangerous. Remember that if you have bronchiectasis, your lungs do not work properly to clear irritants. That means tea tree oil and any possible carrier oils could irritate your lungs and you may not be able to expel it effectively. Also, I was unable to find any information on whether MAC is destroyed by tea tree oil, which means the oil you inhale COULD be contaminated by MAC or other difficult to kill bacteria. Finally, there has been little or no unbiased research on what medications may interact with it. I am a big believer in complementary medicine, and have used herbs, acupuncture, chiropractic and oriental medicine along with contemporary medicine, but only after research regarding safety and effectiveness. There is substantial evidence regarding safety and effectiveness for use of tea tree oil for some skin conditions. There is no actual evidence, other than anecdote and Dr Oz for inhaling tea tree oil. I would give it a pass for now.