Shingles is a viral infection that causes a painful rash. Shingles can occur anywhere on your body. It typically looks like a single stripe of blisters that wraps around the left side or the right side of your torso.

Shingles is caused by the varicella-zoster virus — the same virus that causes chickenpox. After you've had chickenpox, the virus stays in your body for the rest of your life. Years later, the virus may reactivate as shingles.

Shingles isn't life-threatening. But it can be very painful. Vaccines can help lower the risk of shingles. Early treatment may shorten a shingles infection and lessen the chance of complications. The most common complication is postherpetic neuralgia. This is a painful condition that causes shingles pain for a long time after your blisters have cleared.

Contact your health care provider as soon as possible if you suspect shingles, especially in the following situations:

• The pain and rash occur near an eye. If left untreated, this infection may lead to permanent eye damage.
• You're 50 or older. Age increases your risk of complications.
• You or someone in your family has a weakened immune system. This may be due to cancer, medications or chronic illness.
• The rash is widespread and painful.

Anyone who has ever had chickenpox can develop shingles. Most adults in the United States had chickenpox when they were children. That was before the availability of the routine childhood vaccination that now protects against chickenpox.

Factors that may increase your risk of developing shingles include:

• Age. The risk of developing shingles increases with age. Shingles typically occurs in people older than 50. And people over the age of 60 are more likely to experience more-severe complications.
• Some diseases. Diseases that weaken your immune system, such as HIV/AIDS and cancer, can increase your risk of shingles.
• Cancer treatments. Radiation or chemotherapy can lower your resistance to diseases and may trigger shingles.
• Some medications. Drugs that prevent rejection of transplanted organs can increase your risk of shingles. Long-term use of steroids, such as prednisone, may also increase your risk of developing shingles.

Complications from shingles can include:

• Postherpetic neuralgia. For some people, shingles pain continues long after the blisters have cleared. This condition is known as postherpetic neuralgia. It occurs when damaged nerve fibers send confused and exaggerated messages of pain from your skin to your brain.
• Vision loss. Shingles in or around an eye (ophthalmic shingles) can cause painful eye infections that may result in vision loss.
• Neurological problems. Shingles may cause inflammation of the brain (encephalitis), facial paralysis, or problems with hearing or balance.
• Skin infections. If shingles blisters aren't properly treated, bacterial skin infections may develop.

A shingles vaccine may help prevent shingles. People who are eligible should get the Shingrix vaccine, which has been available in the United States since its approval by the Food and Drug Administration in 2017. The Zostavax vaccine is no longer available in the U.S., but other countries may still use it.

Shingrix is approved and recommended for people age 50 and older, whether they've had shingles or not. People who've had the Zostavax vaccine in the past or don't know whether they've had chickenpox may also receive the Shingrix vaccine.

Shingrix is also recommended for people who are 19 years of age and older who have weakened immune systems due to disease or medication.

Shingrix is a nonliving vaccine made of a virus component. It's given in two doses, with 2 to 6 months between doses. The most common side effects of the shingles vaccine are redness, pain and swelling at the injection site. Some people also experience fatigue, headache and other side effects.

The shingles vaccine doesn't guarantee that you won't get shingles. But this vaccine will likely reduce the course and severity of the disease. And it will likely lower your risk of postherpetic neuralgia. Studies suggest that Shingrix offers protection against shingles for more than five years.

Talk to your health care provider about your vaccination options if you:

• Have had an allergic reaction to any component of the shingles vaccine
• Have a weakened immune system due to a condition or medication
• Have had a stem cell transplant
• Are pregnant or trying to become pregnant

The shingles vaccine is used only as a way to prevent shingles. It's not intended to treat people who currently have the disease.

Health care providers usually diagnose shingles based on the history of pain on one side of your body, along with the telltale rash and blisters. Your health care provider may also take a tissue sample or culture of the blisters to send to the lab.

There's no cure for shingles. Early treatment with prescription antiviral drugs may speed healing and lower your risk of complications. These drugs include:

• Acyclovir (Zovirax)
• Famciclovir
• Valacyclovir (Valtrex)

Shingles can cause severe pain, so your health care provider also may prescribe:

• Capsaicin topical patch (Qutenza)
• Anticonvulsants, such as gabapentin (Neurontin, Gralise, Horizant)
• Tricyclic antidepressants, such as amitriptyline
• Numbing agents, such as lidocaine, in the form of a cream, gel, spray or skin patch
• An injection including corticosteroids and local anesthetics

Talk with your health care provider or pharmacist about benefits and potential side effects of any drugs you're prescribed.

Shingles generally lasts between 2 and 6 weeks. Most people get shingles only once. But it's possible to get it two or more times.

Taking a cool bath or using cool, wet compresses on your blisters may help relieve the itching and pain. And, if possible, try to lower the amount of stress in your life.

You may start by seeing your primary care health care provider.

Here's some information to help you get ready for your appointment.

What you can do

When you make the appointment, ask if there's anything you need to do in advance, such as fasting before having a specific test. Make a list of:

• Your symptoms, including any that seem unrelated to the reason for your appointment
• Key personal information, including major stresses, recent life changes and family medical history
• All medications, vitamins or supplements you take, including the doses
• Questions to ask your doctor

Take a family member or friend along, if possible, to help you remember the information you're given.

For shingles, some basic questions to ask your doctor include:

• What's likely causing my symptoms?
• Other than the most likely cause, what are other possible causes for my symptoms?
• What tests do I need?
• Is my condition likely temporary or chronic?
• What's the best course of action?
• What are the alternatives to the primary approach you're suggesting?
• I have these other health conditions. How can I best manage them together?
• Are there restrictions I need to follow?
• Should I see a specialist?
• Are there brochures or other printed material that I can have? What websites do you recommend?

Don't hesitate to ask other questions.

What to expect from your doctor

Your health care provider is likely to ask you several questions, such as:

• When did your symptoms begin?
• Have your symptoms been continuous or occasional?
• How severe are your symptoms?
• What, if anything, seems to improve your symptoms?
• What, if anything, appears to worsen your symptoms?
• Do you know if you've ever had chickenpox?

What you can do in the meantime

Avoid doing anything that seems to worsen your symptoms.