Spikevax Side Effects

Generic name: COVID-19 mRNA (Moderna) vaccine

Medically reviewed by Drugs.com. Last updated on Feb 2, 2025.

Note: This document provides detailed information about Spikevax.

Applies to COVID-19 mRNA (Moderna) vaccine: intramuscular suspension Side Effects associated with COVID-19 mRNA (Moderna) vaccine. Some dosage forms listed on this page may not apply specifically to the brand name Spikevax.

Applies to COVID-19 mRNA (Moderna) vaccine: intramuscular suspension.

Precautions

Be sure to notify your doctor of any side effects that occur after you receive this vaccine.

This vaccine may cause serious allergic reactions, including anaphylaxis, which can be life-threatening and require immediate medical attention. Tell your doctor right away if you have a rash, itching, a fast heartbeat, trouble breathing, trouble swallowing, or any swelling of your hands, face, or mouth after receiving the vaccine.

This vaccine may increase your risk of serious heart problems (eg, myocarditis, pericarditis), especially after you receive the second dose. Check with your doctor right away if you have anxiety, blue or pale skin, chest pain, possibly moving to the left arm, neck, or shoulder, fever, chills, a fast heartbeat, trouble breathing, or unusual tiredness or weakness.

Fainting may occur after you receive this vaccine. You may also have vision changes, numbness or tingling in your arms, hands, or feet, or jerky movements of the arms and legs. Your doctor may want you to be observed after you get the injection to prevent and manage fainting.

This vaccine may not protect everyone who receives it. This vaccine will not treat symptoms of COVID-19 infection if you already have the disease. It is very important that you take precautions to reduce the risk of COVID-19.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Serious side effects of Spikevax

Along with its needed effects, COVID-19 mRNA (Moderna) vaccine (the active ingredient contained in Spikevax) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur while taking COVID-19 mRNA (Moderna) vaccine:

Other side effects of Spikevax

Some side effects of COVID-19 mRNA (Moderna) vaccine may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

For healthcare professionals

Applies to COVID-19 mRNA (Moderna) vaccine: intramuscular suspension.

General adverse events

The most commonly reported side effects included injection site pain, headache, and fatigue.^[Ref]

Cardiovascular

• Frequency not reported: Myocarditis, pericarditis^[Ref]

Dermatologic

• Common (1% to 10%): Rash
• Frequency not reported: Erythema nodosum, erythema, swelling
• Postmarketing reports: Urticaria^[Ref]

Gastrointestinal

• Very common (10% or more): Nausea/vomiting (up to 23.9%)^[Ref]

Nausea/vomiting included Grades 3 and 4 nausea/vomiting.^[Ref]

Hematologic

• Frequency not reported: Axillary mass, lymph node pain, lymphadenitis, lymphadenopathy^[Ref]

Hypersensitivity

• Frequency not reported: Hypersensitivity events
• Postmarketing reports: Anaphylaxis^[Ref]

Immunologic

• Frequency not reported: Herpes zoster infection^[Ref]

Local

• Very common (10% or more): Injection site pain (up to 93.1%), injection site swelling/hardness greater than 25 mm (up to 20.5%), localized erythema/redness greater than 25 mm (up to 19.5%), swelling at the injection site (up to 13.3%)
• Common (1% to 10%): Erythema at the injection site
• Frequency not reported: Delayed injection site pain, injection-site lymphadenopathy, injection site rash, injection site urticaria, vaccination-site lymphadenopathy^[Ref]

Injection site pain included pain, Grade 3.

Localized erythema/redness greater than 25 mm included Grade 3 localized erythema/redness greater than 25 mm.^[Ref]

Musculoskeletal

• Very common (10% or more): Myalgia (up to 61.7%), arthralgia (up to 45.6%), chills (up to 49%)^[Ref]

Arthralgia included arthralgia, Grades 3 and 4.

Myalgia included Grade 3 myalgia.

Chills included chills, Grade 3.^[Ref]

Nervous system

• Very common (10% or more): Headache (up to 70.2%)
• Frequency not reported: Bell's palsy, facial paralysis
• Postmarketing reports: Syncope^[Ref]

Headache included headache, Grades 3 and 4.^[Ref]

Other

• Very common (10% or more): Fatigue (up to 70.1%), use of antipyretic/pain medication (up to 57.3%), axillary swelling/tenderness (up to 39.5%), fever (up to 19%)^[Ref]

Axillary swelling/tenderness included axillary swelling/tenderness, Grade 3.

Fatigue included fatigue, Grade 3 and fatigue, Grade 4.

Fever included Grades 3 and 4 fever.^[Ref]

See also:

Further information

Spikevax side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer