Shingles, or herpes zoster, is an infection caused by the chicken pox virus, Varicella zoster. The shingles vaccine is effective, and like most medications, it carries a risk of side effects.
The Food and Drug Administration (FDA) have certified two shingles vaccines as safe. However, some people have concerns about potential dangers and whether the vaccines are really effective.
In this article, we discuss the safety of shingles vaccines. We also provide information about the different types of vaccine and the short and long term side effects that they can cause.
A shingles vaccination can significantly reduce the risk of developing shingles and related complications, including PHN.
Other complications of shingles can include:
- Eye complications. People with shingles in or around the eye have a risk of developing corneal ulcers, glaucoma, retinal necrosis, and partial or total vision loss.
- Pneumonia. The shingles virus can spread to the internal organs, resulting in a condition called internal shingles. People can also develop pneumonia if the virus infects the lungs.
- Encephalitis. If the shingles virus infects the brain, it can cause severe, life threatening inflammation. Encephalitis, or brain inflammation, can cause memory problems, loss of some motor functions, mood changes, epilepsy, and even death.
A shingles vaccine may cause the following short-term side effects:
- redness, swelling, or itching near the injection site
- tiredness or fatigue
- muscle pain
- stomach pain
According to the CDC, these symptoms usually last for 2–3 days.
Rarely, a person experiences a severe allergic reaction — or anaphylaxis — after getting a shingles vaccine.
The CDC claim that only one or two out of every 1 million people who receive the Shingrix vaccine develop a severe allergic reaction.
Signs of a severe allergic reaction include:
- low blood pressure
- dizziness or lightheadedness
- stomach pain
- difficulty breathing, or wheezing
- swelling of the face, lips, tongue, or uvula, which is a part of the throat
If a person suspects that they or someone nearby is experiencing anaphylaxis, they should seek emergency medical aid.
Anyone in the U.S. who has experienced a severe allergic reaction to the shingles vaccine can report this online, using the Vaccine Adverse Event Reporting System, or by calling 1-800-822-7967.
In rare cases, the live shingles vaccine, Zostavax, can cause a skin rash or shingles.
The rash that occurs with shingles can affect any area of the body, but it often appears as a line of blisters that wraps around the torso.
Within a few days the blisters cluster, and they continue to form for several more days. The blisters can take 2–3 weeks to heal, according to the American Academy of Dermatology.
Other common symptoms of shingles include:
- swollen lymph nodes
- muscle or joint pain
- nausea or an upset stomach
- sensitivity to light
The FDA have approved two shingles vaccines for adults: the recombinant zoster vaccine (Shingrix) and the zoster virus vaccine (Zostavax).
Shingrix is the shingles vaccine that the medical community prefers.
The Centers for Disease Control and Prevention (CDC) claim that Shingrix is over 90% effective at preventing shingles and postherpetic neuralgia (PHN), a common complication that involves long term nerve pain.
A person gets the Shingrix vaccine in two doses. The CDC recommend waiting 2–6 months between the first and second doses.
With some exceptions, adults over 50 should get this vaccine, even if they have already had shingles or a Zostavax vaccine in the past.
Healthcare providers in the United States have administered Zostavax since 2006. This vaccine contains the live shingles virus, and it comes as a single dose.
According to the FDA, Zostavax may reduce the risk of shingles by about 50% in people aged 60 and older and by about 70% in people aged 50–59.
The CDC recommend Zostavax for adults aged 60 and older, with some exceptions.
A person with an allergy to any ingredient in the Shingrix vaccine may want to consider taking the Zostavax vaccine instead.
The FDA have approved the use of both shingles vaccines in healthy adults over the age of 50.
However, there are some instances in which a person should not get either vaccine — if they are pregnant or breastfeeding, allergic to any ingredient in the vaccine, or have a weakened immune system, for example.
Older adults and people with weakened immune systems have a higher risk of developing shingles, according to the National Institutes of Health (NIH).
Adults should get a shingles vaccine if they:
- are at least 50 years old
- do not remember if they have had chicken pox
- do not remember if they have ever had a shingles vaccine
- have already received the Zostavax vaccine
- have a history of shingles
People should not get a shingles vaccine if they:
- have an allergy to any ingredient in the vaccine
- are not immune to the Varicella zoster virus
- currently have shingles
- are pregnant or breastfeeding
- are taking certain antiviral medications
- have a fever of 101.3F or higher
People who test negative for the Varicella zoster virus can get the chicken pox vaccine instead.
A person should avoid the shingles vaccine if they have a weakened immune system due to:
- a medical condition that compromises the immune system, such as AIDS
- cancer that affects the lymphatic system or bone marrow
- cancer treatments, such as radiation or chemotherapy
- medications that affect the immune system, such as steroids
Also, women who are or may become pregnant should avoid the Zostavax vaccine.
The CDC recommend leaving at least a 4-week gap between getting any shingles vaccine and becoming pregnant.
The risk of shingles significantly increases with age. The FDA and CDC recommend that adults ages 50 years and older have one of the two available shingles vaccines: Shingrix or Zostavax.
While most healthy adults can safely receive either vaccine, the medications can cause side effects immediately after injection, including:
- muscle pain
- stomach pain
Side effects should resolve in 2–3 days. People can usually manage their symptoms by resting and taking over-the-counter pain relievers.
Rarely, a person may experience anaphylaxis, a severe allergic reaction, immediately after receiving the Shingrix vaccine.
People should ask about the safety of a shingles vaccine if they:
- have a history of severe allergies or have ever experienced anaphylaxis
- have a weakened immune system
- are pregnant or plan to become pregnant
- take medications that can weaken their immune system