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Shingles vaccine side effects: what is expected and what needs urgent care

Shingrix commonly causes short-lived soreness and flu-like symptoms. Allergy signs and uncommon safety signals need different attention.

Priya Raghavan

By Priya Raghavan · Science Reporter

4 min read

Shingrix, the shingles vaccine currently available in the United States, commonly causes a sore, red or swollen arm along with tiredness, headache, muscle pain, fever, shivering or an upset stomach. The Centers for Disease Control and Prevention says these reactions generally last two to three days, though they can interrupt normal activities.

Expected short-term reactions differ from signs of a severe allergy that need emergency care. Reports of health problems after vaccination also need context: a report alone does not show that the vaccine caused the problem.

The usual pattern after Shingrix

CDC and Cleveland Clinic list these common effects after the shot:

  • Pain, redness or swelling where the injection was given
  • Muscle pain
  • Tiredness
  • Headache
  • Shivering or fever
  • Upset stomach, including abdominal discomfort or nausea

CDC says most effects are mild to moderate and are more common in younger recipients. They may affect normal daily activities for the short period they last.

In eight Shingrix clinical trials involving more than 10,000 participants, 78% reported at least some injection-site pain, according to CDC. Seventeen percent reported a grade 3 vaccination-related reaction, meaning a reaction severe enough to prevent normal activities; about 1 in 10 reported grade 3 injection-site symptoms and about 1 in 10 reported grade 3 whole-body symptoms.

When to get emergency care

Arm soreness, fatigue, fever and stomach symptoms fit the common short-term pattern. CDC says severe allergic reactions after vaccination are rare but can be life-threatening.

Seek emergency medical care for hives; swelling of the face or throat; trouble breathing; a fast heartbeat; dizziness; or weakness. CDC and Cleveland Clinic list these as signs of a severe allergic reaction.

The Shingrix manufacturer also says fainting can occur after injectable vaccines, including Shingrix, and that precautions should be taken to prevent falls and injuries.

Guillain-Barré syndrome safety signal

The Shingrix manufacturer says an increased risk of Guillain-Barré syndrome, or GBS, was observed after vaccination. It describes GBS as severe muscle weakness; the supplied information does not give a risk estimate, so it should not be treated as a common expected reaction.

Persistent or concerning symptoms should be discussed with a healthcare professional rather than assumed to be routine post-shot discomfort.

How to read the safety numbers

  • Clinical trials provide the rates of reactions reported by participants in the studies, including the activity-limiting reactions reported by CDC.
  • Active surveillance collects recipients' experiences soon after vaccination. In an Australian survey of more than 5,500 Shingrix recipients, 52.3% reported no side effects in the first three days. Fewer than 7% missed work, study or routine duties, and fewer than 0.5% reported medical attendance. These were short-term survey findings from participating Australian sites, not universal rates.
  • VAERS, the U.S. Vaccine Adverse Event Reporting System, is an early-warning system co-managed by CDC and FDA. Healthcare providers and manufacturers must report certain events, and patients and caregivers can also submit reports.

A VAERS report records a health problem after vaccination, not proof that vaccination caused it. A post-marketing analysis of reports submitted through April 2024 identified 66,849 reports related to Shingrix, 97.3% of which were classified as non-serious; injection-site reactions, fever, chills and headache were among the commonly reported events. Those totals cannot establish the chance of an event after a dose or prove that Shingrix caused every reported event.

What to expect

For most people, the practical expectation after Shingrix is a sore arm and possibly a brief spell of flu-like or stomach symptoms that resolves within two to three days, according to CDC. Emergency allergy symptoms call for immediate care, while other persistent or concerning symptoms merit a conversation with a healthcare professional.

Frequently asked questions

How long do Shingrix side effects usually last?

CDC says most Shingrix side effects are mild to moderate and last two to three days. They can affect normal daily activities during that period.

When should I seek emergency care after a shingles vaccine?

Seek emergency medical care for hives, swelling of the face or throat, trouble breathing, a fast heartbeat, dizziness or weakness. CDC says severe allergic reactions after vaccination are rare but can be life-threatening.

Do reports to VAERS prove that Shingrix caused a health problem?

No. CDC describes VAERS as an early-warning reporting system that accepts reports of health problems after vaccination, including events whose cause is uncertain. A report alone cannot establish causation or calculate an event rate.

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