Last reviewed: September 29, 2026

It means MRSA was found living in your nose. It is not an infection. It may raise the risk of an infection after surgery, and it changes how you are prepared for it.

Staph bacteria live on everyone’s skin, and most of the time they cause no harm. MRSA is a form of staph that resists some common antibiotics. An infection with MRSA can be very difficult to treat. That is why hospitals look for it before a joint replacement. A swab of the nose is the usual way to find it.

In studies, people who carried MRSA were more likely to develop a joint infection after surgery. In pooled studies of more than 300,000 joint replacements, MRSA carriers were more than twice as likely to develop a joint infection. That was true even after they had been treated to clear it before surgery. So treatment lowers the risk, but it may not bring it back to normal.

Treatment before surgery usually means two things. One is an antibiotic ointment called mupirocin, put inside the nose for several days. The other is washing the body with chlorhexidine, an antiseptic soap. In trials, this combination lowered staph infections after surgery, and it worked best in people known to be carriers.

The antibiotic given at surgery may also change. The usual antibiotic may not work well against MRSA, so carriers are often given vancomycin as well. Adding vancomycin for every patient did not lower infections in a large trial, so it is kept for those who need it, such as MRSA carriers.

According to the American Academy of Orthopaedic Surgeons, treating MRSA carriers with nose ointment before hip and knee replacement is a low-risk, reasonable option.

In general:

  • Use the nose ointment and body wash exactly as instructed, up to the day of surgery.
  • Ask your surgeon whether the antibiotic given at surgery will change because of your swab.
  • Tell your surgeon if you have had an MRSA infection before, anywhere in the body.
  • Redness, drainage, fever or worsening pain after surgery needs to be seen promptly.

Drafted with AI assistance from published sources, reviewed and edited by Babak Sheikh, MD.

Sources:

This is general information about what published research shows. It is not medical advice and it is not about your situation. Reading it does not create a doctor-patient relationship with me. I am a retired orthopedic surgeon and I do not see patients. Talk with your own doctor before changing anything about your care. If something feels suddenly or seriously wrong, get medical care promptly rather than waiting.

This page is provided as is. I make no guarantee that it is accurate, complete or current, and medical evidence changes. Use of it is at your own risk.

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