Brief Answer: all 3 herbs detailed Detailed Answer: Hello, To improve your lung function, you need to do regular deep breathing exercises. You can try the various methods of breathing techniques. There are several of them. All of these exercises basically help in increasing the lung capacity and hence improve lung function. Yes, there are certain herbs that have shown beneficial role on the lungs like Coltsfoot, Elecampane, Mullein, etc. Regarding Pleurisy root, yes, it can be used to improve lung function. However, it needs to be used with caution in patients with pre-existing heart conditions. I see that you have no significant medical history. So, this should not be a problem for you. Blood root, yes, it has no significant side effects except for it can cause glaucoma, an eye condition, when used for long time and at high doses. Short term use is better and improves lung function. Echinacea has more benefits with common cold rather than with lung function. I see that you are healthy with no medical history as such. You may want to try these herbs for short term use. I would suggest you to do deep breathing exercises on a daily basis to improve lung function. Quit smoking, if you do so. It helps significantly in improving the lung function. Wish you good health.

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