Question for OT docs, PAs, NPs and Nurses (NSFW)

My friend, Phil was recently diagnosed with acute bronchitis. He's been to the doctor twice since last Thursday. He told me that he has already taken one round of antibiotics, cough suppressant (at night to help sleep - you can hear his breathing), breathing treatment, air inhaler and a steroid shot.

He went back to the doctor (different one) on Monday. She gave him a breathing treatment, told him to continue using air inhaler, cough suppressant (at night to help him sleep - you can hear his breathing), cough expectorant, and a steroid pack (to be taken over next 6 days).

His symptoms include, coughing (obviously), ears popping, congestion, dripping like a faucet (when not congested) and sneezing. Here's his question.

When he coughs, it continues to be "dry" as in not productive. At what point, if any, should he start to see any phlegm or mucus? By seeing this, would this indicate that the infection is breaking up -- and thus his coughing is then more productive? Or can it just go away without having to see the green? I told him to ask his doctor but he is very shy, similar to Punxsutawney Phil.

Phil thanks you. Here is his gift to you for helping.