My child is 6 months old and is on his second day of azithromycin for severe congestion and coughing. We have attempted to administer the medication today (day-2) and he threw up both times the liquid entered his mouth. He has had diahrea and is pooping about 6-7 times a day since he started the medication. He is still a very happy baby and you would never know by his demeanor that he was sick....however, like I said, he is congested and coughing.