Cephalexin Dosing for Uncomplicated Cellulitis

Adult Dosing Recommendations

The Infectious Diseases Society of America recommends cephalexin 500 mg four times daily (every 6 hours) orally for 5-7 days for adults with uncomplicated cellulitis 1, 2
A duration of 5 days is as effective as 10 days if clinical improvement occurs by day 5 1

β-hemolytic streptococci (particularly group A streptococcus) are the predominant pathogens in typical cellulitis, according to the Infectious Diseases Society of America 1, 3
MRSA is an unusual cause of typical, non-purulent cellulitis, as stated by the Infectious Diseases Society of America 1, 3
A large randomized trial demonstrated that adding trimethoprim-sulfamethoxazole (for MRSA coverage) to cephalexin provided no additional benefit for uncomplicated cellulitis, as reported by the Infectious Diseases Society of America 1
Cephalexin may not be appropriate for cellulitis associated with penetrating trauma, especially from illicit drug use, or presence of purulent drainage or abscess, according to the Infectious Diseases Society of America 1, 4

The Infectious Diseases Society of America recommends that cephalexin is appropriate for penicillin-allergic patients EXCEPT those with immediate hypersensitivity reactions (anaphylaxis, urticaria) 2
Elevate the affected area to promote drainage of edema, and treat predisposing conditions: tinea pedis, venous insufficiency, eczema, as suggested by the Infectious Diseases Society of America 1, 3, 5

The Infectious Diseases Society of America recommends alternative oral β-lactams, including penicillin VK 250-500 mg every 6 hours 2
Amoxicillin 500 mg three times daily is an alternative, as reported by the Infectious Diseases Society of America 4
Dicloxacillin 500 mg four times daily is another option, according to the Infectious Diseases Society of America 1, 2
Clindamycin 300-450 mg four times daily (provides both streptococcal and MRSA coverage) is also recommended by the Infectious Diseases Society of America 1, 2, 4