Shingles (herpes zoster) is a painful, blistering skin rash. It is caused by the varicella-zoster virus. This is the virus that also causes chickenpox.
After you get chickenpox, the virus remains inactive (becomes dormant) in certain nerves in the body. Shingles occurs after the virus becomes active again in these nerves after many years. Many people had such a mild case of chickenpox that they do not realize they have had the infection.
The reason the virus suddenly becomes active again is not clear. Often only one attack occurs.
Shingles can develop in any age group. You are more likely to develop the condition if:
If an adult or child has direct contact with the shingles rash and did not have chickenpox as a child or get the chickenpox vaccine, they can develop chickenpox, not shingles.
The first symptom is usually pain, tingling, or burning that occurs on one side of the body. The pain and burning may be severe and are usually present before any rash appears.
Red patches on the skin, followed by small blisters, form in most people:
Other symptoms may include:
You may also have pain, muscle weakness, and a rash involving different parts of your face if shingles affects a nerve in your face. The symptoms may include:
Your health care provider can make the diagnosis by looking at your skin and asking about your medical history.
Tests are rarely needed, but may include taking a skin sample to see if the skin is infected with the virus.
Blood tests may show an increase in white blood cells and antibodies to the chickenpox virus. But the tests cannot confirm that the rash is due to shingles.
Your health care provider may prescribe a medicine that fights the virus, called an antiviral drug. This drug helps reduce pain, prevent complications, and shorten the course of the disease.
The medicines should be started within 72 hours of when you first feel pain or burning. It is best to start taking them before the blisters appear. The medicines are usually given in pill form. Some people may need to receive the medicine through a vein (by IV).
Strong anti-inflammatory medicines called corticosteroids, such as prednisone, may be used to reduce swelling and pain. These medicines do not work in all patients.
Other medicines may include:
Follow your health care provider's instructions about how to care for yourself at home.
Other measures may include:
Stay away from people while your sores are oozing to avoid infecting those who have never had chickenpox -- especially pregnant women.
Herpes zoster usually clears in 2 to 3 weeks and rarely returns. If the virus affects the nerves that control movement (the motor nerves), you may have temporary or permanent weakness or paralysis.
Sometimes the pain in the area where the shingles occurred may last from months to years. This pain is called postherpetic neuralgia.
It occurs when the nerves have been damaged after an outbreak of shingles. Pain ranges from mild to very severe. Postherpetic neuralgia is more likely to occur in persons over age 60.
Complications may include:
Call your health care provider if you have symptoms of shingles, particularly if you have a weakened immune system or if your symptoms persist or worsen. Shingles that affects the eye may lead to permanent blindness if you do not receive emergency medical care.
Do not touch the rash and blisters on persons with shingles or chickenpox if you have never had chickenpox or the chickenpox vaccine.
A herpes zoster vaccine is available. It is different than the chickenpox vaccine. Older adults who receive the herpes zoster vaccine are less likely to have complications from shingles.
Cohen J. Varicella-zoster virus (chickenpox, shingles). In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 24th ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 383.
Habif TP. Warts, herpes simples, and other viral infections. In: Habif TP. Clinical Dermatology. 5th ed. St. Louis, MO: Elsevier Mosby; 2009:chap 12.