How to Tell If a Cut Is Infected

Oozing, Hot Nasty Injuries are Almost Never Good

Updated June 27, 2017
Child showing her grazed knee
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An infected cut can lead to a serious illness if left untreated. In many cases, skin infections like staph, strep, or MRSA get started from the tiniest of cuts. Even a little cut that doesn't need stitches can cause big problems if it gets infected and goes untreated. So, how can you tell if a cut is infected?

Signs of Infection

To tell if a cut is infected, look for these signs:

  • Swelling
  • Redness
  • Local fever (the cut feels hot compared to areas around it)
  • Draining pus (the cut is oozing thick, gooey stuff)

If a cut or scrape becomes infected, you need to see a healthcare provider. In most cases, only doctors, physician assistants or nurse practitioners can give you antibiotics to fight the infection. Untreated, infected wounds can become serious.

The worst case scenario is that an infected cut develops into a full-body (systemic) infection. To tell if you are developing a bigger infection, look for:

  • Fever over 100 degrees Fahrenheit taken orally or rectally. It's one thing if the cut is hot, but when the whole body has a fever it means the infection is spreading.
  • Body aches, especially in joints and areas not adjacent to the injury. It's understandable if your cut is sore, but the rest of you shouldn't be.
  • Nausea or diarrhea are both indicators that an infection has moved from the local injury to affect other body systems (specifically, the gastrointestinal system).

    Keep It Clean

    To avoid an infected cut, it's important to keep cuts clean as they heal. Most of the time, soap and water are all you need. Whether you use an antibiotic ointment or not is up to you, but it's really not necessary. 

    It helps to cover a cut with an adhesive bandage, but remember to change the bandage every day and wash the cut with soap and water.

    A Job for the Doctor

    If you have an infected cut or are developing a systemic infection, see a doctor. Once a cut gets infected, you're going to need a doctor's help. Once an infection is identified, antibiotics will be necessary to eliminate it.

    There are several antibiotics available, and different antibiotics work on different bacteria. To figure out which drug is right for your situation, the physician might need to swab your injury and send the swab to be cultured, which basically means it will be left to grow for up to three days. As soon as the bacteria grow enough to be seen under a microscope the exact type will be identified—assuming they grow. If nothing grows, the cut is not infected and no antibiotics will be needed.

    If the physician, physician's assistant or nurse practitioner does prescribe antibiotics, take them all. Often, you'll start to feel better within a day or two of beginning your antibiotic regimen and you might be tempted to stop taking them. Don't do it. Even though you feel better, the antibiotics haven't killed all the bacteria yet. If you stop, the bacteria that had successfully survived the first few days of antibiotics will reproduce. These are the stronger bacteria, and their offspring will be much more resistant to that antibiotic.

    Source:

    Roodsari, G. (2015). The risk of wound infection after simple hand laceration. World Journal Of Emergency Medicine, 6(1), 44. doi:10.5847/wjem.j.1920-8642.2015.01.008