What is cephalexin used for? This eMedTV page explains that this prescription antibiotic can treat bacterial infections and prevent heart valve infections. It can also be a substitute for penicillin if a person is allergic to that particular drug. Do not try Levaquin! I am allergic to penicillin and was given Levaquin and within 10 minutes it sent me into anaphylactic schock. Needless to say I was immediately rushed to the emergency room for treatment. 160 mg trimethoprim/800 mg sulfamethoxazole PO every 12 hours. The Infectious Diseases Society of America (IDSA) recommends a 3 day treatment course for acute, uncomplicated cystitis and a 14 day treatment course for pyelonephritis in female patients. OBJECTIVES • Understand the definition and epidemiology of uncomplicated, non-purulent cellulitis. • Understand the most common microbial causes of non-purulent cellulitis. User Reviews for Bactrim to treat Bacterial Skin Infection. The following information is NOT intended to endorse drugs or recommend therapy. While these reviews might be helpful, they are not a substitute for the expertise, skill, knowledge and judgement of healthcare practitioners in patient care. Bacitracin may not be effective on keflex for cellulitis cellulitis strong enough to cause abscesses. Also inform about possible cases of liver, kidney and intestinal disorders or asthma. The term cellulitis is commonly used to indicate a nonnecrotizing inflammation of the skin and subcutaneous tissues, a process usually related to acute infection that does not involve the fascia or muscles. Cellulitis is characterized by localized pain, swelling, tenderness, erythema, and warmth. Cellulitis is a common infection caused by bacteria. Several types of bacteria can cause the condition. Staphylococcus and streptococcus bacteria are the common ones culprits, however. Cellulitis definition identifies it as a condition more than a disease. Staph bacteria strain is majorly responsible for the infection. However, a number of other bacteria types can also cause the infection. Cellulitis is a common infection of the skin and the soft tissues underneath the skin. Bacterial skin infections and soft tissue infections occur when bacteria invade broken or normal skin and start to spread under the skin and into the soft tissues.