Shingles is a painful rash caused by the same virus that causes chickenpox. If you had chickenpox as a child, that virus never actually left your body. It stayed dormant in your nerve cells for years or even decades, and shingles is what happens when it wakes back up. About 1 in 3 people in the United States will develop shingles at some point in their lifetime.
Why the Chickenpox Virus Reactivates
After you recover from chickenpox, the virus travels along your nerves and settles into clusters of nerve cells near your spine and skull. There, it goes silent. Within about four to eight weeks of the original infection, the virus stops replicating, and your immune system can no longer detect it. It essentially hides inside your neurons, with most of its genes switched off.
The virus can remain dormant for decades. Exactly what triggers it to reactivate isn’t fully understood, but the pattern is clear: it happens most often when your immune system weakens. Aging is the biggest factor. Your body’s ability to keep the virus suppressed declines naturally over time, which is why shingles becomes far more common after age 50. Stress, illness, certain medications that suppress the immune system, and conditions like cancer or HIV also raise the risk. When the virus reactivates, it travels back along the nerve fibers to the skin, producing the characteristic rash.
What the Rash Looks and Feels Like
The hallmark of shingles is a rash that appears in a band or strip on one side of your body. This pattern follows the path of a single nerve, which is why it typically wraps around one side of your torso or appears on one side of your face. It almost never crosses the body’s midline.
Before the rash shows up, you’ll usually feel pain, tingling, or burning in that area for a few days. Then clusters of small, fluid-filled blisters develop. New blisters keep forming over three to five days before the rash begins to dry out and scab over. The whole process from first blister to healed skin takes about two to four weeks, though some people end up with permanent discoloration or scarring.
The pain can range from mild itching to intense, burning sensations. Some people describe it as feeling like an electric shock or a deep ache. For many, the pain is the worst part of the experience, not the rash itself.
Shingles Without a Rash
In rare cases, shingles causes pain along a nerve path without ever producing visible blisters. This is called zoster sine herpete. You feel the same burning, one-sided pain, but there’s no rash to explain it. This makes diagnosis tricky. Standard blood tests for the virus only detect it in about 60% of these cases. Newer approaches, including testing skin scrapings from the painful area even when the skin looks normal, can sometimes confirm the diagnosis.
How Shingles Is Treated
Antiviral medications are the first line of treatment. Starting them early, ideally within the first 72 hours after the rash appears, can shorten the outbreak and reduce the risk of complications. These drugs don’t kill the virus outright, but they stop it from replicating, giving your immune system a chance to regain control.
Pain management is often just as important as the antiviral treatment. Over-the-counter pain relievers help with mild cases, but moderate to severe shingles pain frequently requires stronger options. Doctors commonly prescribe nerve pain medications (the same ones used for conditions like epilepsy or fibromyalgia) because standard painkillers don’t always work well against nerve-based pain. Topical treatments applied directly to the skin can also provide some relief.
The Risk of Lasting Nerve Pain
The most common complication of shingles is postherpetic neuralgia, a condition where pain persists in the affected area long after the rash has healed. It’s defined as pain lasting three months or more after the initial outbreak and is often described as burning or stabbing.
Age is the biggest predictor. People under 50 rarely develop severe lasting pain. But around 13% of shingles patients aged 50 and older go on to develop postherpetic neuralgia. The numbers climb steeply with age: roughly 60% of shingles patients at age 60 experience it, rising to 75% at age 70. For most people, the pain gradually fades. About 5% of patients still have it at three months, and 3% at one year. In some cases, though, the pain lasts for years or even becomes permanent.
Can You Spread Shingles to Others?
You can’t give someone shingles directly. However, the fluid inside shingles blisters contains active virus. If someone who has never had chickenpox or the chickenpox vaccine comes into direct contact with that fluid, or breathes in virus particles from the blisters, they can catch chickenpox (not shingles). That person could then develop shingles later in life.
The contagious window is specific: you can only spread the virus while the blisters are open. Before the rash appears and after the blisters scab over, there’s no risk. Keeping the rash covered with a bandage reduces the chance of exposing others.
Vaccination and Prevention
The shingles vaccine (Shingrix) is the most effective way to prevent an outbreak. It’s recommended for adults 50 and older, as well as younger adults with weakened immune systems. The vaccine is given as two doses, spaced a few months apart.
The protection is strong. In adults aged 50 to 69 with healthy immune systems, the vaccine is 97% effective at preventing shingles. In adults 70 and older, effectiveness is 91%. For preventing postherpetic neuralgia specifically, the numbers are 91% in people over 50 and 89% in people over 70. Even in adults with weakened immune systems, the vaccine provides between 68% and 91% protection depending on the underlying condition.
You can get the vaccine even if you’ve already had shingles. Having one episode doesn’t guarantee immunity, and repeat outbreaks are possible. The vaccine can also be given to people who aren’t sure whether they ever had chickenpox, since more than 99% of Americans born before 1980 carry the virus whether they remember having chickenpox or not.