Cellulitis will cause swelling and redness and and on the legs or deep involvement can have a dark color. This needs treatments with antibiotics either orally or in more severe cases with intravenous antibiotics. In cases of cellulitis without draining wounds or abscess, streptococci continue to be the likely etiology, and beta-lactam antibiotics are appropriate therapy, as noted in the following: In mild cases of cellulitis treated on an outpatient basis, dicloxacillin, amoxicillin, and cephalexin are all reasonable choices. Cellulitis cause the affected skin to turn red, get hot, slightly swollen, and tender. Untreated, it can spread & become very serious, so get it treated.