mycoplasmic pneumonia possible, because has hives with cough and ear infection. Hives seem worse, even though has been on 2 doses of zithromax. took 2.5 tsp yesterday (1st day), and 1.5 today. Now whole body covered with hives. Should I expect improvement with the two day dose? Cough same, no ear complaints, but hives worse. Could she be reacting to zithromax?