Shingles, or herpes zoster, is a painful rash caused by the varicella-zoster virus (VZV). This is the same virus that causes chickenpox.

This virus remains dormant (inactive) in a part of your nervous system called the dorsal root ganglion. It can be reactivated during times of stress or illness, or when the immune system is weakened by an autoimmune disease or cancer.

The risk of developing shingles is relatively low for healthy young adults — about 4 out of 1,000 people in the United States, according to the Centers for Disease Control and Prevention (CDC). It’s much higher for those above age 60. Shingles affects about 1 out of 100 people in this older age group, the CDC says.

Generally, a case of shingles rash resolves within 3 to 4 weeks. It can resolve without treatment, but antiviral treatment can shorten both the duration and severity of the rash.

This refers to the typical course a shingles rash takes, even with antiviral treatment:

  1. A person may develop a tingling sensation or pain in a certain area on the skin, most commonly on the waistline. This may last for several days.
  2. Next, a rash develops in the area. The skin turns red, with fluid-filled bumps (vesicles). It’s during this time that a shingles rash can spread the VZV to another person who hasn’t had chickenpox or the chickenpox vaccine.
  3. After 1 to 2 weeks, these fluid-filled bumps start to crust over. At this point, the rash can no longer spread to other people. It can then take 1 to 2 more weeks for the crusted areas to fully scab over and heal.

It’s a good idea to see a doctor whenever you have a case of shingles, no matter how mild.

Prompt antiviral treatment not only decreases the duration and severity of the rash but can also decrease the chance of developing post-herpetic neuralgia. Post-herpetic neuralgia is a complication of shingles characterized by long-term, debilitating pain.

If your rash has mostly healed, it’s still a good idea to see a doctor so they can monitor the rash for changes or complications, such as a bacterial skin infection that forms on top of your existing rash. This is known as a superimposed infection.

The fluid-filled bumps will stop oozing and crust over. Then, the scabs will go away within 1 to 2 weeks. The shingles rash is no longer contagious when the bumps stop oozing. However, the rash isn’t fully healed until the scabs are gone.

Yes, it’s important to start antiviral treatment within 72 hours of first developing a rash. This can shorten the course of the rash as well as decrease its severity.

Shingles cannot be spread over different areas of your body. For example, if you have an active shingles rash on your back, the fluid from the blisters cannot cause a new rash on your arm.

However, the fluid could potentially spread VZV to someone else if they’ve never had chickenpox or received the chickenpox vaccine.

One caveat here is that some people can develop disseminated herpes zoster, which is when the shingles virus causes a rash over multiple areas of the body. This can happen in people who have weakened immune systems from autoimmune disease, cancer, or immunosuppressant medications.

While most cases of shingles are mild, several potential complications may require emergent care:

  • Facial rash. A shingles rash on the face is concerning because eye involvement can lead to blindness. This requires an urgent assessment from an ophthalmologist.
  • Loss of hearing or facial movement. Rarely, shingles can lead to hearing loss or facial nerve paralysis.
  • Disseminated herpes zoster. This widespread shingles rash can also affect your organs. It requires hospitalization with intravenous (IV) antiviral treatment.
  • Fever. Shingles in addition to fever can be concerning. It may mean you have a superimposed bacterial infection, which could require antibiotics and close observation.
  • Confusion or seizures. Shingles in addition to confusion or seizures could indicate brain inflammation, which requires hospitalization for IV antiviral treatment and close monitoring.

Dr. Megan Soliman is an ABMS board certified internal medicine physician whose main focus in her clinical practice is patient advocacy. Her research interests include adverse effects of medications and herbal supplements. Soliman is enthusiastic about “bread and butter” medicine, which includes treating patients with the most common diseases. She also has a passion for reaching underserved communities, including both U.S. and international rural communities.