Hello and welcome to HCM.
I have gone through your question.
You have not mentioned Z pack which he took contained 3 doses or 5 doses.It is because he may need antibiotics for few more days.
If I were your treating doctor,I would recommend,
-Tablet Augmentin/
erythromycin for 5-7 days (prescription drug)
-Cough expectorant syrup and
analgesic antipyretic like
paracetamol for 3 days.
-Steam inhalation.
-salt water gargles.
-Plenty of rest and intake of water.
-healthy diet including lots of fruits and vegetables of different colours for Vitamin A.
-If the symptoms worsens beyond 3 days ,go for further investigations like throat swab microscopy and culture,chest X ray.Further management depends on these investigations.
-Report immediately if there is onset of high grade fever,
shortness of breath,diarrhea.
Hope this information helps.
Thanks and regards.