hi i have hives for 11 days now,i was on antibiotics called ciproxin and at he end of the course i started to get hives which i thought was an allergic reaction so i got an antihestimine called histek allergy,this stopped the itching and some hives went but im still getting some too,this morning i had 4 new ones,one behind each knee,on my thigh and upper leg,iv been on and off antibiotics now since june.