Which antibiotic is better for uti? known allergy is to cipro. prescribed keflex. how long to take affect. fever still around 100 -102.4 after 4hrs of 1st pill. doing as old to alternate 1000mg tylenol & 800mg ibuprofen every 4hrs. 44yr male. thanks?

Hard to say: The best way to anticipate success of an antibiotic is to have a culture of the germ where sensitivity is tested. Without that, you rely on clinical change. The germ in these infections has had a head start creating the problem. I would expect a decline in fever within 24/36 hrs after starting the med as a good sign it will work. I would not expect it to change the symptoms in 4 hours.