Shingles, also known as zoster or herpes zoster, is a viral infection caused by the varicella-zoster virus (VZV). This is the same virus that causes chickenpox.
Anyone who’s had chickenpox can get shingles. After you’ve been infected with chickenpox, VZV lies inactive in your body — mostly in spinal or cranial nerves — usually for many decades. If the virus reactivates, it can travel along nerve pathways to your skin and cause a painful rash.
Shingles is very rarely life-threatening, but it can be exceedingly painful. If you’re over 50 or over 18 and immunocompromised, you can get a
shingles vaccine to help prevent it.
Signs and Symptoms of Shingles
Shingles usually appears as a single strip of blisters around the left or right side of your body. It’s almost always unilateral, meaning it involves only one side of your body.
Shingles tends to show up most frequently on your torso, just because of the laws of probability, says Joseph Safdieh, MD, a professor of neurology at Weill Cornell Medicine in New York City.
In that area of your body, there are more nerves that can host the virus. But you can get a
shingles rash anywhere: on your feet, your buttocks, your legs, even your genital area.
Often, it’s not what the rash looks like, but what it feels like before and after it shows up, that signals the condition. Up to several days before the shingles rash appears, pain, itching, or tingling often occurs in the area where it will develop.
In the days before the rash appears, a variety of other flu-like
symptoms of shingles can occur. You may experience:
- Chills
- Fever
- Headache
- Upset stomach
You may even experience the pain but not the rash. Because the pain of shingles originates in the nerves, it may have a different quality than any other pain you have experienced before.
“Neuropathic pain is burning,” says Dr. Safdieh. “It’s both numb and painful at the same time, and can be provoked by touching the skin.” Your skin may be so sensitive that even sunlight can bring on a stabbing sensation.
Causes and Risk Factors of Shingles
Initial exposure to VZV causes chickenpox, not shingles. A shingles infection can only occur if you’ve recovered from chickenpox or, in rare cases, after receiving the chickenpox vaccine.
After a chickenpox infection, VZV lies inactive in your body, mainly in spinal or cranial nerves. It’s not clear why, but sometimes the virus reactivates, and that’s when it travels along the nerves to erupt as a rash on your skin, causing shingles.
The following may also put you at increased risk of developing shingles:
You may have heard that someone got shingles because they were stressed, but there’s not much scientific evidence to confirm this connection.
If there is a link between stress and shingles, it’s probably not that the stress itself is putting a strain on your immune system; it may be that stress creates conditions that lower immunity. Keep in mind, says Safdieh, that you’re likely not sleeping or eating well when you’re stressed. “All these factors can play a role.”
How Is Shingles Diagnosed?
Once the rash appears, the signs and symptoms are usually clear enough for a doctor to make a diagnosis. Before the rash appears, or in cases where there is no rash, diagnosis is more challenging.
In cases with a less typical set of symptoms (pain without a rash, for example), lab testing can be helpful in confirming a diagnosis. A polymerase chain reaction (PCR) test may be used to detect varicella-zoster virus DNA in a skin lesion sample. Saliva samples may also be examined, but they're less reliable for herpes zoster than for varicella zoster.
Herpes zoster is sometimes confused with herpes simplex, the virus that causes cold sores. Skin symptoms may also be mistaken for other rash-causing conditions, like impetigo, contact dermatitis, and psoriasis.
Treatment and Medication Options for Shingles
There’s no cure for shingles. But if you get immediate treatment, it can help speed the healing process and reduce your risk of complications.
Medication Options
Several options are available to treat shingles symptoms. The most common types of medication include:
- Antivirals Drugs such as valacyclovir (Valtrex) can help shorten the duration and severity of shingles. Antivirals are most effective if you start them as quickly as possible after the rash appears.
- Pain Medication Prescription or over-the-counter (OTC) drugs may help bring relief.
- Topical Creams Numbing or calming salves may help ease itching and burning.
- Corticosteroids These anti-inflammatories help reduce swelling.
Alternative and Complementary Therapies
Home remedies may help soothe itching and burning from a shingles rash. Try:
- Oatmeal baths
- Wet compresses
- Stress-reduction techniques
Prevention of Shingles
The best way to prevent shingles is by getting the
shingles vaccine, Shingrix. It’s approved for adults age 19 and older with weakened immune systems and anyone over 50 years old.
Sales of an older, less effective vaccine, Zostavax, were discontinued in 2020. Even if you’ve already had shingles, received Zostavax, or aren’t sure whether you ever had chickenpox, you should still get the Shingrix vaccination.
Shingles can’t be passed between people, but VZV can spread to people who aren’t immune to chickenpox — meaning those who have not been
vaccinated against chickenpox or have not had the disease.
VZV can spread from person to person through direct contact with the open sores of the shingles rash when blisters are present.
So until your shingles blisters turn into scabs, you’ll be able to pass the virus on to others. The following steps can help keep you from spreading the virus:
- Keep the rash covered.
- Avoid touching or scratching the rash.
- Wash your hands often.
- If possible, stay away from vulnerable people (like infants and pregnant people).
How Long Does Shingles Last?
Before a shingles rash appears, you may have pain, itching, or tingling, along with headache and other symptoms, for several days.
Once the rash emerges, new blisters form over the course of three to five days, and progressively dry out and crust over. The blisters usually heal in two to four weeks.
However, about 10 to 18 percent of people develop long-term nerve pain from shingles, called postherpetic neuralgia (PHN). This may last months or even years.
Complications of Shingles
PHN is the most common shingles complication. The pain, which can be severe, is located in the areas where the shingles rash was, even after the rash disappears. Risk of PHN increases with age, as does the severity and duration of the pain. It’s uncommon in people under 40.
Other complications can include:
- Eye complications, including loss of vision, can occur
- Bacterial infection of shingles lesions
- Rare complications include the development of pneumonia, hearing problems, encephalitis (swelling of the brain), and death
