Smallpox and Mpox Vaccine, Live
Why get vaccinated?
Smallpox and mpox vaccine, live may prevent smallpox and mpox that may occur with infection due to orthopoxviruses.
Infection with orthopoxviruses can cause the following: life-threatening skin rashes and lesions, muscle aches, fever, swollen lymph nodes.
Smallpox and mpox vaccine, live contains a live virus that has been weakened so it does not cause disease but canstill stimulate the body to make antibodies against the virus to provide a defense against potential infection.
How is the vaccine given?
Smallpox and mpox vaccine comes as a suspension (liquid) to be given subcutaneously (under the skin) by a healthcare provider.
Smallpox and mpox vaccine is given as two doses given 4 weeks apart.
What should you tell the person who is giving the vaccine?
Tell your vaccine provider if you:
- have had an allergic reaction to this vaccine, any part of this vaccine, any other vaccine or any drug, food or substance. Tell your vaccine provider about the allergy and what symptoms you had.
- are immunocompromised due to a medical condition or treatment.
- are pregnant or breastfeeding.
In some cases, your health care provider may decide to postpone vaccination to a future visit.
What are the risks from vaccination?
Side effects that have been reported with smallpox and mpox vaccine include:
- pain, redness, swelling, itching, or thickening of the skin near the site of injection
- headache
- tiredness
- muscle pain
Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately or get emergency medical treatment:
- rash, hives, difficulty breathing or swallowing
People sometimes faint after medical procedures, including vaccination. Tell your provider if you feel dizzy or have vision changes or ringing in the ears.
Adverse reactions should be reported to the Vaccine Adverse Event Reporting System (VAERS). Your health care provider will usually file this report, or you can do it yourself. Visit https://vaers.hhs.gov or call 1-800-822-7967. VAERS is only for reporting reactions, and VAERS staff members do not give medical advice.
How can I learn more?
- Read the Vaccine Information Sheet (VIS) that your vaccine provider will give you or you can obtain it at https://www.cdc.gov/vaccines/hcp/current-vis/index.html
- Ask your healthcare provider.
- Call your local or state health department.
This report on medications is for your information only, and is not considered individual patient advice. Because of the changing nature of drug information, please consult your physician or pharmacist about specific clinical use.
The American Society of Health-System Pharmacists, Inc. represents that the information provided hereunder was formulated with a reasonable standard of care, and in conformity with professional standards in the field. The American Society of Health-System Pharmacists, Inc. makes no representations or warranties, express or implied, including, but not limited to, any implied warranty of merchantability and/or fitness for a particular purpose, with respect to such information and specifically disclaims all such warranties. Users are advised that decisions regarding drug therapy are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and the information is provided for informational purposes only. The entire monograph for a drug should be reviewed for a thorough understanding of the drug's actions, uses and side effects. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information is not a substitute for medical care.
AHFS® Patient Medication Information™. © Copyright, 2026. The American Society of Health-System Pharmacists®, 4500 East-West Highway, Suite 900, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.
Selected Revisions: July 15, 2026.
