Common brand names: Keflex, Biocef.
Description: Cephalexin is a cephalosporin-type antibiotic closely related to penicillins.
Dental Uses: It is occasionally used to treat dental infections that are resistant to penicillin VK. However it must be stressed that most dental infections can be better and less expensively treated with penicillin VK.
The other use of cephalexin in dentistry is to prevent joint infections in certain patients with prosthetic joints of the hip, knee or elbow who are scheduled to undergo dental procedures likely to induce mucosal or gingival bleeding. Such procedures include dental extractions, periodontal surgery, professional cleanings, orthodontic band (not bracket) placement and some other procedures.
Dosages for dental purposes: The typical adult dose of cephalexin for dental infections is 250 milligrams to 500 milligrams every six hours for seven to 10 days.
The recommended dose of cephalexin for patients at risk of joint infections is 2 grams (four 500-milligram capsules) an hour before the dental procedure. This single-dose regimen is generally well tolerated.
Concerns and possible side effects: Cephalexin produces a higher incidence of abdominal pain, diarrhea, nausea and vomiting than penicillin VK.
Approximately 10 percent of patients allergic to penicillins also are allergic to cephalosporins. Allergic reactions can range from a mild rash to life-threatening closure of the airway and a fall in blood pressure. Cephalosporins must be avoided or used with extreme caution in patients with documented penicillin allergies.