What Causes Skin Rashes While Having Treatment For Stomach Viral Infection?

Hello Doctor. 4 months ago after having bronchitis and finished an antibiodic shortly after I broke out in hives on my stomach, arms. Did the dermotologist route and tests along with a bioposy on one of them that was came back as a general hive. I just got over a stomach virus with vomitting and diarehea and am now breaking out again. Is this possibly just a reaction to this virus?