If you had chickenpox as a child, you might recall the itchy, spotted rash that popped up on your face and body. The varicella zoster virus that causes chickenpox stays inside your body for many years.
Once you're older, that same virus can wake up and cause shingles, also called herpes zoster. It gives you a rash, too, but it's often more painful than itchy.
A blistering rash on one side of your body can be a sign you have it. See your doctor to find out for sure. Once you've been diagnosed, you can get treated to help relieve your rash and other symptoms.
The Telltale Signs
Your doctor will first ask whether you've had chickenpox and look at your symptoms. A rash is the main sign of shingles. Often your doctor can tell that you have it from your skin alone.
Other conditions also cause rashes that look like shingles. Your doctor might check to see if you have:
Contact dermatitis: A skin reaction caused by an allergy to latex, metals, chemicals, or drugs
Candida infection: It comes from a type of yeast called Candida
Dermatitis herpetiformis: A rash that some people with celiac disease can get
Impetigo: A skin infection caused by bacteria
Insect bites: Sometimes, they can look like shingles
Folliculitis: The tiny holes that hairs grow out of can get inflamed
Scabies: A skin condition caused by a small bug called a mite
One way to tell shingles from these conditions is by the other symptoms that come with it. You can also have:
Tests
Doctors rarely test for shingles unless the rash alone isn't enough to make a diagnosis. Some people get tested because they're at higher risk for complications. You might have a test done if you:
- Are about to have an organ transplant
- Have a weakened immune system
- Are going to begin a drug that lowers your immune system
Doctors use two types of tests to diagnose chickenpox or shingles:
Antibody: When you're exposed to varicella zoster, your immune system makes proteins to fight it. Your doctor can look for these proteins, called antibodies, in a sample of your blood. They take the sample from a vein in your arm. These tests might be able to tell whether you have chickenpox now or have had it in the past, but the results are often hard to interpret.
Viral detection: This test can find out if varicella zoster virus is present in the rash. Your doctor can collect samples from scabs from blisters that have crusted over.
Your doctor should have the results in 1 to 3 days. You might need to have a second test if the results aren't clear.
Your symptoms and test results will show whether you have shingles. Once you've been diagnosed, you can start on treatment to help you feel better.