SS:
I'm going to take a big leap and try to answer this. LOL. I don't know if it would depress your breathing or suppress your cough. I do know of something that would help IF you have a person who can do it for you. My nephew kept really bad pneumonia caused from asthma all the time. We could cup our hands and smack him on the back. Not real hard, just all over....repeatedly. Small cupping of hands, not fingertips jamming. It will help loosen up the stuff in the lungs and is easier to cough up. I don't know about your living situation, but perhaps you have someone who could do this for you?
At one time we had a little blue suction cup looking thing his doctor gave him to use on the back but said the slight cupping of your hand hitting the back would do the same thing. If you need more explanation, let me know.
BTW: Are you receiving antibiotics under a physician's care? IF not you really should, it can progress to pneumonia if it hasnt already.
Please take care and good luck!
Kimberly.