Understanding Cold Sores -- Treatment

Medically Reviewed by Debra Jaliman, MD on May 16, 2023
2 min read

To see if you have the herpes simplex virus (HSV), which causes cold sores, your doctor may simply examine the cold sore or may take a culture from it.

The doctor may also test blood for antibodies to the virus.

A positive antibody test only proves that you have the virus; it does not indicate whether or not the virus is active or when you may have acquired it.

You can't cure HSV or a cold sore, but you can alleviate the pain it causes by avoiding spicy or acidic foods, applying ice, and using over-the-counter remedies. Look for medicines that contain numbing agents such as phenol and menthol to reduce cracking and soften scabs. Abreva is an over-the-counter topical remedy used to help speed healing and minimize pain from a cold sore. It must be used many times a day to speed the healing.

If your cold sore is especially painful or irritating, your doctor may prescribe an anesthetic gel to alleviate pain or an antiviral oral medication to speed healing or prevent recurrence. The antiviral medicines available for treatment include acyclovir (Zovirax), famciclovir (Famvir), and valacyclovir (Valtrex). These oral medications are more effective when started within the first 48 hours of the outbreak. Valacyclovir is more expensive, but is better absorbed in the digestive tract and therefore more reliable. Acyclovir and another antiviral medication called penciclovir (Denavir) also come in a topical form.

Cold sores can become complicated by a bacterial infection, so it is also important to keep them clean by washing gently with soap and water as needed.

 

  • Wash your hands after touching a cold sore.
  • Don't rub your eyes after touching your cold sore; you could develop an ocular herpes infection, which may lead to blindness if left untreated.
  • Don't touch your genitals after touching your cold sore; you could develop genital herpes.
  • Replace your toothbrush.
  • Don't kiss someone who has a cold sore or use that person's utensils, towels, or razors.
  • Apply sunscreen to the face and lips before prolonged exposure to the sun.
  • Replace your lipstick or lip balm.