The main Dharma practice we should apply when we have lung is that of transforming problems into the path to enlightenment. There are many books that deal with this, an especially good one being Lama Zopa Rinpoches's 'Transforming Problems into Happiness'. However, I found that some, mind transformation (lo-jong) practices were not good for my lung, so people should check individually, since each person and each case of lung is different. For example, when I tried to practice tong-len (taking and giving meditation), it made the lung worse. When I later received the advice of Lama Zopa Rinpoche, he didn't advise me to practice tong-len, which showed that it was not appropriate to practice it at that time. One practice maybe be helpful at a certain time, yet not at others.
by Ven. Thubten Shakya
(excerpt from Balanced Mind, Balanced Body)