Herpes zoster (shingles)

What is herpes zoster (shingles)?

Herpes zoster is also known as shingles. It is caused by the varicella-zoster virus, the same virus that causes chickenpox. After someone has had chickenpox the virus can remain inactive (or hidden) within nerve cells near the spine for many years. Sometimes the virus reactivates (awakens) and it travels along your nerves to the skin, causing a painful blistering rash in the part of the skin supplied by those nerves.

What does shingles look and feel like?

The first sign of shingles is often a burning, tingling, or stabbing pain in one area of your body. At this stage you may feel unwell and have a high temperature and headache. You may notice that the lymph nodes (glands under the skin) next to the area affected are enlarged and tender to touch. 
 
A rash usually follows two to three days later, appearing as a crop of red spots. The spots turn in to fluid filled blisters within a day or two and then form crusts or scabs which dry out within about a week.  It usually takes two to three weeks for the scabs to fall off and the skin to heal, sometimes with scarring or changes in skin colour.

Shingles can affect any part of your skin. The most common pattern is a band of skin on your back or chest, or one arm or leg, usually involving just one side of the body. Occasionally, shingles can affect your eyes.

What causes shingles?

The exact cause of shingles reactivation (awakening) is unknown; it is more common in people over 50, particularly those over 70. A recent illness, even a mild one, can temporarily weaken your immune system and trigger shingles. 

Several additional factors can weaken your immune system and increase your risk of having shingles or lead to more severe shingles, these include:

• Medical conditions - HIV infection, leukaemia, lymphoma and some other types of cancer
   
• Medication which weakens the immune system - chemotherapy and other cancer treatments, long-term steroids, and drugs used to prevent rejection after an organ transplant. Certain medicines, usually prescribed by a hospital specialist, which are used to treat long-term medical conditions may also increase the risk of shingles. You will be told if your medication weakens your immune system
   
• Stress - is likely to be a trigger in some people

Is shingles infectious (contagious)?

You cannot catch shingles from someone who has shingles or from someone who has chickenpox. Shingles happens because of reactivation of the virus already in your own nerves.

You can catch chickenpox (which is the same virus) from someone who has shingles if you have not had chickenpox before. 

Shingles is infectious from when the first blister appears until they have all crusted over, which usually takes one to two weeks.

Things you can do to help yourself

• Apply cool compresses to the rash to help soothe the pain
• Wear loose-fitting clothing made from natural fibres like cotton to avoid irritating the rash
• Over-the-counter pain relievers, such as paracetamol and ibuprofen, can help manage pain
• If you have a high temperature or you feel unwell you may need to rest for a few days and take time off work
• You should avoid close contact with newborn babies, elderly people, pregnant women who have not already had chickenpox and people with weakened immune systems

Make an appointment at your GP surgery

It's important to contact your GP surgery as soon as possible if you think you have shingles. Medicines to treat the virus (anti-viral medicine), for example aciclovir, can be used to treat shingles. Early diagnosis and treatment can help shorten the duration of the illness and reduce the risk of complications, such as long-term nerve pain (post-herpetic neuralgia). The anti-viral medicine works best if it is started with 3 days of the rash appearing.

Complications of shingles

If shingles affects your eye it will usually cause a painful red eye. If you think you eye may be infected you must contact your GP or other health care professional immediately. If not treated quickly shingles can affect your vision permanently. Your doctor may arrange for you to see an eye specialist (ophthalmologist) on the same day. 

In about one in twenty people, muscles in the area of skin affected by shingles may become weak. This can affect muscles in the face when the shingles appears on facial skin. When this happens you can expect improvement or complete recovery in the months ahead.  

Pain in the area affected by shingles can go on after the person has recovered from the infection; if it continues for longer than one month it is called post-herpetic neuralgia. This is more common in elderly people. The pain may feel burning or stabbing. Some people experience tingling, itching or numbness, or the skin may feel supersensitive to touch. 
Post-herpetic neuralgia can be treated with a local anaesthetic ointment (lidocaine 5% ointment) or a painkilling cream called capsaicin cream. Stick-on patches containing a local anaesthetic sometimes help. Standard painkillers are usually not very effective. Other oral medications may be prescribed by your healthcare professional. Drugs including some antidepressant medicines and drugs normally used for treating epilepsy are commonly used in much smaller doses for this kind of pain and can be prescribed by your healthcare professional.

How to prevent shingles

There are two vaccines available for shingles.  Even if you have had a vaccine against shingles it is still possible to get shingles but if you do, the infection is usually less severe. The most recent shingles immunisation programme offers immunisation to these groups of people:

• Those aged 50 years old and above who have a weakened immune system
• People who turn 65 on or after 1 September 2023
• All people aged 70-79

The shingles vaccine is available all year round. You should be automatically invited to have your vaccination when you turn the relevant eligible age. The shingles vaccine will not help someone who has active shingles or post-herpetic neuralgia.
Click here for more details on the UK shingles vaccination programme.

Other resources

Further information on herpes zoster can be found as follows:

• In the A-Z of Skin Conditions
• The Shingles Support Society 

Helping with other skin conditions 

If you, a family member, or friend have an undiagnosed skin condition; or you want to learn more about how to treat skin conditions, please Take the Tour of the PCDS Website so you can learn how best to use this website.