Shingles, or herpes zoster, is a viral infection caused by the same virus that causes chickenpox. After a person recovers from chickenpox, “the virus remains dormant in nerve tissue” and can reactivate years later. Shingles mostly affects older adults or anyone with a weakened immune system. It isn’t usually life-threatening, but it can be very painful and may cause long-term nerve issues if untreated.

The condition usually begins with tingling, burning, or stabbing pain on one side of the body. A rash appears within days, often on the torso, face, or chest, turning into “fluid-filled blisters that crust over.” Symptoms can include skin sensitivity, mild fever, and fatigue. Some people develop lingering nerve pain known as postherpetic neuralgia.

Shingles isn’t highly contagious, but the virus can spread to anyone who has never had chickenpox through direct contact with blister fluid.

Treatment works best when started early. Antiviral medications like acyclovir or valacyclovir can reduce how severe and how long the illness lasts. Pain relief may include over-the-counter medicine, prescription options, or soothing topical care such as cool compresses and calamine lotion.

Prevention is especially important for older adults. A vaccine is recommended for people over 50 or those with weakened immunity. While it doesn’t fully eliminate risk, “it significantly reduces the chance of an outbreak” and can make symptoms milder if shingles does occur.

If you’ve had chickenpox and suddenly develop nerve pain or a blistering rash, seek medical care quickly. Early treatment improves recovery and reduces complications.