mycoplasma pneumonia recovery

My cat had an alarming chest x-ray after I brought him in for coughing and sneezing. Besides that he is very healthy and eats and drinks and maintains his weight. He is deduced to have mycoplasma pneumonia. He was put on doxycycline, and has been taking it for about a week now. After a few days, the biggest change I noticed was that he started sounding very phegmy and seemed to be coughing up a lot more mucus and a lot more frequently than before. He is still very mucusy and when i listen to his breathing wtih my ear against his chest, I can hear a sort of wheezing in his lungs. SO, I am wondering if he is actually recovering and the doxy is helping to break up what was in his lungs and I just have to wait for it to clear up,  or if I should be concerned by this change and see the vet immediately? Thank you.

[Cliff Redford, DVM]

Sorry for the late reply.
As the saying goes "better out then in" and I expect these signs are due to a loosening of the infection and your cat is now expelling debris from his lungs. When in doubt, always ask your orginal vet as they will know the case.