Postherpetic Neuralgia (PHN)

Shingles is an infection caused by the same virus that causes chickenpox, the varicella zoster virus, but not everyone who had chickenpox will develop shingles. Once a person has chickenpox, the virus can stay "quiet" in their nerve tissue for years. But for some people, the virus "awakens" and forms blisters on the skin. The shingles virus can cause a few blisters or an extensive rash that can occur on one side of the body or face1.

Once the shingles rash has healed, some people may experience severe pain in the same area of the rash as well as beyond that area. This pain is called postherpetic neuralgia (PHN), or after-shingles pain1. In the United States, approximately one million people will develop shingles every year2. Approximately 10-18% of people with shingles will go on to develop PHN1,3.

PHN pain is thought to result from nerve damage caused by the shingles virus. The pain usually appears in the area of the shingles rash, but the size of the PHN pain region can vary considerably1. In some people, PHN pain can last for months or even years1,3.

If you think you may have shingles, you should talk to your healthcare professional. Receiving medical treatment for shingles as soon as possible can lessen the time you have shingles and lower your risk for postherpetic neuralgia (PHN) or after-shingles pain.


  1. Cure PHN: Your Questions Answered. VZV Research Foundation, Inc. 2004: 1-6. Available at: Accessed October 14, 2014.
  2. Harpaz R, Ortega-Sanchez IR and Seward JF. Prevention of Herpes Zoster: Recommendations of the Advisory Committee on Immunization Practices (ACIP). Morbidity and Mortality Weekly Report. 2008; 57(05): 1-30. Available at Accessed October 14, 2014.
  3. Weaver BA. Herpes Zoster Overview: Natural History and Incidence. J Am Osteopath Assoc. 2009;109(suppl 2):S2-S6.

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