Hi, Keflex contains cephalexin which belongs to the group of medications known as cephalosporin antibiotics is used to treat bacterial infections like urinary tract infections, bladder infections, pneumonia and other respiratory diseases, typhoid, skin and soft tissue infections, eye infections, ear infections and many more. It works by killing the bacteria affecting the patient or by preventing their growth. Keflex may cause painful ripping sensation around belly button area or intense abdominal cramps as a common side effects. Other side effects of Keflex are nausea, vomiting, diarrhea, heartburn, indigestion, rectal or genital itching, dizziness, extreme tiredness, feeling of pins and needles on skin, headache, joint pain, low energy, agitation, confusion, weakness, muscle pain, loss of appetite, red skin lesions, red and irritated eye, sore throat, ulcers or white spots in the mouth or on the lips, blistering or peeling of the skin, dark urine, cough, clay or light colored stools, allergic reactions etc. If any of these side effects persist for long or bother you, then you should consult your doctor for medical attention. Take care. Hope I have answered your questions. Let me know if I can assist you further. Regards, Dr. Zubayer Alam, General And Family Physician