Antibiotic Prophylaxis After Total Joint Replacement for Dental Procedures
Keflex (cephalexin) is NOT recommended for prophylaxis after total joint replacement when undergoing dental procedures, and in fact, antibiotic prophylaxis of any kind is not routinely indicated for most patients with total joint replacements undergoing dental work. 1, 2
Primary Recommendation
The joint advisory statement from the American Urological Association (AUA) and American Academy of Orthopaedic Surgeons (AAOS) clearly states that antibiotic prophylaxis is not routinely indicated for most patients with total joint replacements on that basis alone. 1 This applies to dental procedures as well, where the American Dental Association and AAOS have concluded that prophylaxis is not indicated for dental patients with pins, plates, or screws, nor is it routinely indicated for most dental patients with total joint replacements. 2, 3
The most recent high-quality evidence from a 2017 systematic review in Acta Orthopaedica definitively concluded that prophylactic antibiotics should not be prescribed to patients with normal or impaired immune system function to prevent dental hematogenous periprosthetic joint infection (HPJI). 4 This review found no evidence that antibiotic prophylaxis reduces the incidence of dental HPJI. 4
High-Risk Patients Who May Warrant Consideration
While routine prophylaxis is not recommended, a small subset of high-risk patients may warrant consideration for premedication. These include patients who meet BOTH of the following criteria 1:
Patient Risk Factors:
- Immunocompromised states (inflammatory arthropathies, drug-induced immunosuppression, radiation-induced immunosuppression) 5
- HIV infection/AIDS 5
- Active malignancy 5
- Type 1 diabetes mellitus 5
- Previous prosthetic joint infection 5
- Malnourished patients 5
- Hemophilia 5
- Solid organ transplant recipients on immunosuppression 5
Timing Considerations:
- The first 2 years after joint replacement is the most critical period for hematogenous seeding 1
Why Cephalexin (Keflex) Is Not the Appropriate Choice
Even in the rare high-risk patient where prophylaxis might be considered, cephalexin is not the recommended agent. The AUA/AAOS guidelines specify that when prophylaxis is indicated for urological procedures in high-risk patients with total joint replacements, the recommended regimens are 1:
- Fluoroquinolones: Ciprofloxacin 500 mg, levofloxacin 500 mg, or ofloxacin 400 mg orally 1-2 hours preoperatively 1, 5
- IV regimen: Ampicillin 2 g IV (or vancomycin 1 g IV over 1-2 hours for penicillin allergy) plus gentamicin 1.5 mg/kg IV given 30-60 minutes preoperatively 1, 5
Cephalexin is listed in the antimicrobial dosing tables as a first-generation cephalosporin at 500 mg PO every 6 hours 1, but it is not among the specifically recommended agents for prophylaxis in this clinical scenario.
Important Clinical Considerations
The rationale against routine prophylaxis is compelling: Bacteremias from dental procedures are no more likely to cause prosthetic joint infections than bacteremias from normal daily activities such as tooth brushing and chewing. 1 The risk of antibiotic-associated adverse events exceeds the benefit from prophylactic therapy. 1
Common pitfall to avoid: Do not prescribe routine prophylaxis for all patients with joint replacements undergoing dental work, as this contributes to antibiotic resistance without providing benefit. 5, 4
Best practice: Patients should maintain good oral hygiene and visit the dentist regularly rather than relying on antibiotic prophylaxis. 4
Evolution of Guidelines
The guidelines have evolved significantly as understanding of prosthetic joint infection pathophysiology has improved. 6 Earlier recommendations were more liberal with prophylaxis, but current consensus based on evidence is that prophylaxis should be targeted only to the highest-risk patients rather than administered routinely. 5, 2