What is shingles?

Shingles is a skin complaint caused by the same virus that causes chickenpox - the herpes zoster virus. Shingles occurs as a painful rash on the body and face.

A burning sensation on the skin may be experienced as the rash begins to develop. A few days after pain begins, the patient may become feverish and their lymph glands may become enlarged. When the rash appears, it resembles the chickenpox rash, although it generally covers a smaller area of skin. The rash affects a strip of skin overlying one nerve, most commonly on the trunk. The blisters burst and become sores after another few days. They then take a couple of weeks to scab over.

Sometimes, the area that the rash covered becomes tender and painful even after the scabs have healed. The sensation is particularly unpleasant, and is known as post-herpetic neuralgia.

How do you catch shingles?

Shingles is a reactivation of the chickenpox virus. In order to contract the disease, you must have previously come into contact with chickenpox. After a bout of chickenpox, the virus hibernates within the body, like its close family member, the herpes simplex virus (causing cold sores). Shingles occurs when the herpes zoster virus is reactivated, and travels to the skin’s surface.

It is unclear why the virus becomes reactivated, but it seems that an immune deficiency may be a factor. As the efficiency of the immune system declines with age, older people are more likely to develop shingles. Shingles may also follow a stressful episode. People with HIV are particularly prone to shingles. Patients who have undergone chemotherapy are also more likely to develop shingles.

Shingles rarely causes any lasting difficulties, though the rash can be very uncomfortable. For the majority of patients, shingles clears up completely after about a month. However, medical attention may be required if the rash appears on the face, or near the eyes. A facial rash may cause temporary loss of hearing, and facial spasms. Shingles near the eyes may scar the cornea of the eye, affecting clarity of vision. You may also wish to consult your GP if the sores have not scabbed over after ten days, or if you have another illness as well as shingles.

How is shingles treated?

There are anti-viral drugs that can halt the development of shingles, but as with the cold sore virus, the drugs must be started as soon as possible to have a useful effect. After the rash has developed, the drugs are of very limited value. Keeping the rash uncovered as much as possible allows air to get at the sores, and helps them to heal quicker. It is important not to scratch the sores as this will spread the rash, and may cause bacteria to infect the rash.

Calamine lotion may ease the itching, and any analgesic (aspirin, paracetamol, etc) may be used to dull any pain. If this is not sufficient, your GP can decide to give you stronger painkillers.

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Reviewed: November 20, 2006