Understanding Mupirocin and Its Role in Nasal Health
Mupirocin is a topical antibiotic medication available by prescription [1.2.1]. While it also comes as a cream for skin infections like impetigo, the nasal ointment form is specifically designed for use inside the nostrils [1.2.7]. Its primary purpose is a process called nasal "decolonization." This means it works to eradicate or eliminate colonies of specific bacteria that can live in the nasal passages, most notably Staphylococcus aureus [1.4.1].
Many people carry this bacterium without getting sick, a state known as being a "carrier" [1.3.2]. In fact, about 30% of the population carries staph in their nose [1.5.5]. While often harmless, this nasal colony can become a source of infection for the carrier or spread to other, more vulnerable individuals [1.4.7]. This is particularly risky in healthcare settings, where patients may have weakened immune systems or be undergoing surgery [1.4.3].
The Primary Target: Staphylococcus aureus and MRSA
The main reason a doctor prescribes intranasal mupirocin is to target Staphylococcus aureus, commonly known as staph [1.4.1]. More specifically, it is a frontline treatment for eliminating methicillin-resistant Staphylococcus aureus (MRSA) from the nose [1.7.6].
- Staphylococcus aureus: A common bacterium that can cause a range of illnesses, from minor skin infections to life-threatening conditions like pneumonia and bloodstream infections [1.4.2].
- MRSA: A strain of staph that has developed resistance to many of the antibiotics commonly used to treat ordinary staph infections. MRSA nasal carriage is a significant concern in hospitals as it increases the risk of hard-to-treat hospital-acquired infections (HAIs) [1.7.1].
By decolonizing the nose before a medical procedure, such as orthopedic or cardiac surgery, clinicians can significantly reduce the patient's own bacteria from entering a surgical wound and causing a post-operative infection [1.3.2, 1.7.1]. It is also used during hospital outbreaks to control the spread of MRSA among patients and healthcare workers [1.4.3].
How to Properly Use Mupirocin Nasal Ointment
Correct application is crucial for the medication to be effective. The typical course of treatment is twice a day (morning and evening) for five days [1.3.1].
- Wash Hands: Always wash your hands with soap and water before and after application [1.3.1].
- Prepare the Ointment: The ointment usually comes in a single-use tube [1.3.1]. You will use about half of the tube for each nostril.
- Apply to Nostril: Squeeze approximately half of the ointment from the tube directly into one nostril. Repeat for the other nostril with the remaining ointment [1.3.1]. Some instructions may suggest using a cotton swab [1.3.2].
- Distribute the Ointment: Gently press the sides of your nose together and release them repeatedly for about one minute. This massaging action helps spread the ointment throughout the inside of the nostrils [1.3.1, 1.3.3].
- Discard: Throw away the single-use tube after application [1.3.1]. Do not save it for the next dose.
It is important to complete the full 5-day course, even if you feel fine, to ensure the bacteria are fully eradicated [1.2.2]. Do not use it for longer than prescribed, as long-term use is not recommended [1.2.1].
Potential Side Effects and Considerations
While generally safe, mupirocin nasal ointment can have side effects. The most common ones are localized to the nose.
- Common Side Effects: Headache, runny or stuffy nose, sore throat, cough, and a change in taste [1.6.2]. Itching, burning, or stinging in the nose may also occur [1.6.3].
- Less Common/Serious Side Effects: If you experience a severe rash, hives, difficulty breathing, nosebleeds, or severe irritation, stop using the medicine and contact your doctor immediately. These could be signs of an allergic reaction [1.6.3].
This medication is for use only in the nose. Avoid getting it in your eyes; if this happens, rinse thoroughly with water [1.2.2].
Mupirocin vs. Alternative Nasal Antiseptics
While mupirocin is a well-established standard for nasal decolonization, concerns about antibiotic resistance have led to the use and study of alternatives [1.7.1, 1.8.5].
| Treatment | Type | Mechanism & Use | Considerations |
|---|---|---|---|
| Mupirocin | Antibiotic Ointment | Inhibits bacterial protein synthesis to kill S. aureus [1.4.5]. Standard 5-day course is highly effective [1.8.5]. | Prescription required. Risk of developing bacterial resistance with widespread or repeated use [1.7.1, 1.8.5]. |
| Povidone-Iodine | Antiseptic Solution/Swab | Broad-spectrum antiseptic that kills bacteria on contact. Often used as a one-time application before surgery. | A promising alternative to mupirocin due to lower resistance risk [1.8.4]. May require application at least an hour before surgery for best effect [1.8.1]. |
| Chlorhexidine | Antiseptic | Often used for skin cleansing (body wash) in combination with a nasal agent, but can be used in the nose [1.7.1, 1.8.3]. | Less effective than mupirocin for nasal use alone. Risk of resistance emergence exists with extensive use [1.7.1, 1.8.3]. |
| Alcohol-Based Antiseptics (ABA) | Antiseptic Gel/Swab | Kills bacteria quickly. Applied pre-operatively. | Considered a viable and sometimes superior alternative to mupirocin and iodophor for reducing surgical site infections [1.8.1]. Can be applied without a long wait time [1.8.1]. |
| Octenidine HCl | Antiseptic Gel | An alternative antiseptic with broad activity [1.8.6]. | Some studies suggest it is less effective at decolonization than mupirocin or neomycin, though it may still help reduce infection rates [1.8.6]. |
The Growing Issue of Mupirocin Resistance
One of the biggest challenges with mupirocin is the emergence of mupirocin-resistant S. aureus [1.7.1]. Resistance can be low-level or high-level. High-level resistance can lead to treatment failure, meaning the ointment will not successfully clear the bacteria from the nose [1.7.4]. This risk is why healthcare facilities have strict protocols for its use and why antibiotic stewardship—the practice of using antibiotics wisely to curb resistance—is so critical [1.8.4]. Using mupirocin only when necessary and completing the full course as prescribed helps minimize the development of resistant strains.
Conclusion
Putting mupirocin in your nose is a targeted antibiotic therapy to eliminate Staphylococcus aureus (including MRSA) colonies from the nasal passages [1.2.1, 1.4.7]. This process of decolonization is a crucial infection control strategy, primarily used to reduce the risk of surgical site infections and control the spread of dangerous bacteria in healthcare environments [1.4.3, 1.7.1]. While effective, its use must be managed carefully to combat the growing threat of antibiotic resistance, with antiseptic alternatives like povidone-iodine and alcohol-based products gaining traction as valuable options [1.8.1, 1.8.4]. Always use this medication exactly as prescribed by a healthcare professional to ensure its benefits and minimize risks.
For more information on MRSA prevention, consider visiting the CDC's page on MRSA.
