Shingles is a painful rash caused by varicella zoster, the same virus responsible for chickenpox.

If you had chickenpox as a child, the virus hasn’t completely gone away. It hides dormant in your body and can reemerge many years later as shingles.

About 1 in 3 people in the United States will develop shingles in their lifetime. This is why vaccination is important. But you should also be prepared for possible side effects. In this article, we’ll discuss the side effects, and talk about who should get the vaccine.

Older adults are most likely to develop shingles. This is why the shingles vaccine is recommended for people ages 50 and older.

Shingrix is the only shingles vaccine approved by the U.S. Food and Drug Administration (FDA).

The Shingrix vaccine is a recombinant vaccine. This means vaccine manufacturers created it by altering and purifying DNA that creates an immune response to fight the virus.

The CDC recommends Shingrix for the prevention of shingles and related complications. The Shingrix vaccine is also recommended for anyone who has already gotten another type of shingles vaccine.

Currently, the CDC recommends healthy people ages 50 and older get the Shingrix vaccine. Doctors administer the vaccine in two doses, which are given 2 to 6 months apart.

The Shingrix vaccine has high success rates in protecting people against shingles.

The Shingrix vaccine is as much as 90 percent effective in preventing shingles. The same is true for Shingrix and postherpetic neuralgia.

People should get the shingles vaccine if they:

  • are 50 years old or older
  • are uncertain if they have or haven’t had chickenpox in the past
  • have a history of shingles
  • have received the Zostavax vaccine in the past

No maximum age exists for when a person can get the Shingrix vaccine.

There are a couple of factors to consider before getting the shingles vaccine:

Allergies

The shingles vaccine contains ingredients that can cause an allergic reaction in some people.

Avoid the Shingrix vaccine if you:

  • have had a severe reaction to the first dose of the Shingrix vaccine
  • have had a severe allergy to one of the components of the Shingrix vaccine
  • have shingles currently
  • are currently breastfeeding or pregnant
  • received a negative test result for the varicella zoster virus

If a person tests negative for the virus, they should get the chickenpox vaccine instead.

Fever

If you have a minor viral illness (like a common cold), you can still get the Shingrix vaccine. But if you have a temperature higher than 101.3°F (38.5°C), wait to get the Shingrix vaccine.

Weakened immune system

People with an immune system weaker than normal do need to be careful. In very rare cases, people who have a weakened immune system have gotten sick from the varicella zoster virus contained in the vaccine.

Talk with your doctor if you suspect that you have a weakened immune system.

Mild side effects

Doctors have tested the shingles vaccine on thousands of people to ensure its efficacy and safety. Most of the time, the vaccine is safely administered without any side effects.

But some people can experience side effects from the Shingrix vaccine, like:

  • muscle pain
  • headache
  • fever
  • stomach pain
  • nausea

These side effects may last between 2 and 3 days after receiving the vaccine.

People have also reported injection-site side effects that include:

  • redness
  • swelling
  • itching
  • soreness

If you do experience side effects after receiving the shingles vaccine, you can take an over-the-counter pain medication in most cases to reduce your symptoms.

Serious side effects

In very rare cases, people have developed a severe allergic reaction to the shingles vaccine. This reaction is called anaphylaxis.

Signs of anaphylaxis include:

  • swelling of the face (including the throat, mouth, and eyes)
  • hives
  • warmth or redness of the skin
  • trouble breathing or wheezing
  • dizziness
  • irregular heartbeat
  • rapid pulse

If you have any of these symptoms after getting the shingles vaccine, seek medical help right away. Anaphylaxis can be life-threatening.

If you or a loved one do experience severe side effects, contact the Vaccine Adverse Event Reporting System at 800-822-7967.

Does the shingles vaccine contain thimerosal?

You may be concerned about additives to the shingles vaccine, like thimerosal.

Thimerosal is a preservative that contains mercury. It’s added to some vaccines to prevent bacteria and other germs from growing in them. The shingles vaccine contains thimerosal.

The worry about thimerosal arose when early research linked it to autism. This connection has since been found to be untrue.

After getting the shingles vaccine, it’s perfectly safe for you to be around friends and family members — even children. People rarely develop a chickenpox-like rash on their skin after they’ve been vaccinated, though it is possible.

If you get this rash, you’ll want to cover it. Make sure any babies, young children, or people who are immunocompromised and haven’t been vaccinated against chickenpox don’t touch the rash.