<s>[INST] I was told that I have cellulitis by my doctor just a couple of days ago and I ve been prescribed Keflex but now the infection has spread from just the lower part of my leg to my knee on my other leg and my thigh. Should I go to a hospital, be tested, etc.? [/INST] This should be promptly evaluated, as the bacteria causing your infection may not be sensitive to the Keflex. You might need a different antibiotic. Contact your doctor and let him/her know what is going on, and get seen at emergency or urgent care. If you are having fevers, this is especially important. It is very concerning that infection has spread to your other leg. You might have resistant bacteria such as MRSA that require aggressive treatment. Cellulitis can get into the bloodstream and cause serious disease. Hope this helps. </s>