@dispatchpat Did he give any indication why he was thinking mycoplasma (pneumonia)? Like lung congestion or ground glass appearance on an x-ray? If so, in someone with suspected MAC, doxycycline is the drug of choice.

Like @cwal, I would prefer a culture first, but with bronchiectasis we are susceptible to it with any kind of respiratory flare. And he may have good reason to suspect and treat it. As a matter of fact, my pulmonologist has given me an open Rx for doxy, to be used if I have a flare that seems to be deteriorating into a lung infection. My instructions are to fill the Rx and start taking it while waiting for a consult (either in person or virtual) with her. And further, "Don't go to Urgent Care and let them give you azithromycin."