photo of woman applying ointment to cold sore

How Are Cold Sores Diagnosed?

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

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

A positive antibody test only proves that you have the virus; it does not tell you if the virus is active or when you were infected.

What Are the Treatments for Cold Sores?

You can't cure HSV or a cold sore, but you can ease 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
  • Menthol to reduce cracking and soften scabs 
  • Abreva, an over-the-counter topical remedy can help speed healing and keep your pain at a minimum. 

Keep in mind that over-the-counter medicines must be used many times a day to speed healing.

If your cold sore is especially painful or irritating, your doctor may prescribe an anesthetic gel to ease discomfort. They can also give you an antiviral oral medication to speed healing or prevent recurrence.

Oral medicationswork better if you start taking them within the first 48 hours of your outbreak. Valacyclovir may cost more, but your digestive tract absorbs it better, making it more reliable.

It's important to keep your cold sore clean because bacteria can infect your sore. Clean and gently wash your cold sore with soap and water as needed to prevent infection.

How Can I Prevent Cold Sores?

  • 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 after your cold sore heals.
  • 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 going out into the sun.
  • Replace your lipstick or lip balm after your sore goes away.

Show Sources

Photo Credit: Moment/Getty Images

SOURCES: 

Columbia University College of Dental Medicine: "Cold Sores and Fever Blisters."

Mayo Clinic: "Cold Sore."

Academy of General Dentistry: "What Are Cold Sores?"

MedlinePlus: "Herpes – oral."