Postherpetic neuralgia is a pain that persists in some people who have had shingles. It often eases and goes over time. Medication can often ease the pain.

Introduction postherpetic neuralgia

Postherpetic neuralgia (PHN) is a nerve pain (neuralgia) that persists after a shingles rash has cleared. If the pain goes, but then returns at a later date, this too is called PHN.

Shingles is an infection of a nerve, and causes a typical rash. It is caused by the varicella-zoster virus. About 1 in 5 people have shingles at some time in their life. Shingles can occur at any age, but it is most common in people aged over 50. Most people with shingles have pain, but the pain usually eases soon after the rash clears. PHN is pain that persists.

How common is postherpetic neuralgia?

PHN is unusual in people aged under 50, and if it does occur it tends to be mild. PHN is more likely to develop, and is more likely to be severe, in people aged over 60. About 1 in 4 people aged over 60 who have shingles develop PHN that lasts more than 30 days. The older you are, the more likely it is that it will occur. However, early treatment of shingles can reduce the risk of developing PHN.

What are the symptoms of postherpetic neuralgia?

PHN causes pain on and around the area of skin that was affected by the shingles rash. The pain is mild or moderate in most cases. However, the pain is severe in some cases.

The pain is usually a constant, burning, or gnawing pain. In addition to, or instead of this, you may have sharp or stabbing pains that come and go. The affected area of skin is often very sensitive. Even slight touch may cause pain, such as the rubbing of clothes or a draught of air on the affected area. You may also have reduced sensation to touch, and be itchy over the affected area.

Why does the pain persist in some people?

Shingles causes inflammation of the nerve. Pain can be expected whilst the rash and inflammation occur. However, it is not clear why some people continue to have pain when the inflammation has gone. It is thought that some scar tissue next to the nerve, or in the nearby part of the spinal cord, may be a factor. This may cause pain messages to be sent to the brain.