Why get vaccinated?

Anthrax vaccine may prevent Anthrax disease that may occur with infection due to Bacillus anthracis.

Infection with Bacillus anthracis can cause the following:

• skin disease (infection enters through the skin by coming into contact with the bacteria spores) which can appear as itchy, small blisters or bumps on skin that can turn into painless, swollen sores with black center (most commonly seen on neck, face, arms or hand)
• respiratory disease (infection enters through the lungs by inhaling the bacteria spores) that can cause fever and chills, heavy sweats, chest pain or cough or shortness of breath, confusion or dizziness, nausea or vomiting or stomach pain, headaches and/or body aches, extreme tiredness
• gastrointestinal disease (infection enters through the stomach but eating contaminated meat) that can cause fever, chills, swelling of neck or glands, sore throat or hoarseness or painful swallowing, nausea, vomiting (including vomiting blood), diarrhea or bloody diarrhea, headache, red face or eyes, stomach pain or swelling, fainting

Anthrax vaccine does not contain the bacteria. It works by triggering the body to makeantibodies against the bacteria to provide a defense against potential infection.

Anthrax vaccine may be given to individuals at high risk of exposure to the bacteria (pre-exposure prophylaxis) or to individuals who have been exposed to the bacteria but have not yet developed the disease to keep them from developing the disease (post-exposure prophylaxis).

How is the vaccine given?

Anthrax vaccine comes as a suspension (liquid) to be given subcutaneously (under the skin) or intramuscularly (into the muscle) by a healthcare provider.

Anthrax vaccine is given as 2 or more doses depending on if it is being given for pre- or post-exposure prophylaxis and how it is being given:

• pre-exposure prophylaxis as an intramuscular injection: give initial dose and then 2 additional doses 1 and 6 months later. If continued exposure risk exists, a booster dose is given 6-12 months after the last dose and then every 12 months after that.
• pre-exposure prophylaxis as a subcutaneous injection: give initial dose and then given 3 additional doses 2 weeks, 4 weeks and then 6 months after. If continued exposure risk exists, a booster dose is given 6-12 months after the last dose and then every 12 months after that.
• post-exposure prophylaxis as a subcutaneous injection: give initial dose and then 2 more doses at 2 and 4 weeks after.

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.
• have had Anthrax disease in the past.
• have a weakened immune system due to a condition or medication you are receiving.
• are pregnant or thinking about becoming pregnant. If you discover you are pregnant after receiving the vaccine, call your doctor right away. Anthrax vaccine may cause harm to the fetus. Talk to your vaccine provider about the risks and benefits of receiving this vaccine if you are pregnant.
• are breastfeeding. Effects of Anthrax vaccine on lactation or presence in breast milk is not known.

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 Anthrax Vaccine include:

• warmth, tenderness, itching, pain, redness or bruising at the site of injection
• difficulty lifting or moving arm after receiving the injection
• tiredness
• fever
• headache
• muscle aches or pains
• swelling of lymph nodes

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately or get emergency medical treatment:

• rash, shortness of breath or difficulty breathing, swelling of face or throat

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.

Brand name(s)

• Biothrax^®

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: June 15, 2026.