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Anthrax vaccine

Generic name: anthrax vaccine [ ANTH-rax-vax-EEN ]
Brand name: Biothrax
Dosage form: injectable suspension (-)
Drug class: Bacterial vaccines

Medically reviewed by on Dec 6, 2021. Written by Cerner Multum.

What is anthrax vaccine?

Anthrax is a serious disease that can spread quickly throughout the body and it is fatal in a high number of cases, especially when acquired through the lungs.

Anthrax vaccine is used to help prevent anthrax disease in adults. Anthrax vaccine will not treat an active infection that has already developed in the body.

Anthrax vaccine is used before exposure in people who may come into contact with anthrax bacteria in certain work settings, while traveling, or during military service. Anthrax vaccine is used together with antibiotics after exposure in people who have already come into contact with anthrax bacteria.

This vaccine works by exposing you to an antigen protein that causes your body to develop immunity to the disease. Anthrax vaccine does not contain live or killed forms of the bacteria that causes anthrax.

Like any vaccine, the anthrax vaccine may not provide protection from disease in every person.


Use only as directed. Tell your doctor if you use other medicines or have other medical conditions or allergies.

Before taking this medicine

You should not receive this vaccine if you have ever had a life-threatening allergic reaction to an anthrax vaccine.

Tell your doctor if you have ever had:

May harm an unborn baby. Tell your doctor if you are pregnant.

If you are pregnant, your name may be listed on a pregnancy registry to track the effects of anthrax vaccine on the baby.

Ask a doctor if it is safe to breastfeed while using anthrax vaccine.

How is anthrax vaccine given?

This vaccine is given as an injection (shot) into a muscle or under the skin.

Anthrax vaccine is recommended before exposure for adults age 18 through 65 in the following situations:

  • people who handle anthrax bacteria in a laboratory or other work setting;

  • people who handle animal hides or furs imported from areas where anthrax is common;

  • people who handle meat or other animal products in areas where anthrax is common;

  • veterinarians who travel to countries where anthrax is common; and

  • military personnel at risk of exposure through potential biological warfare when anthrax may be used as a weapon.

When used after exposure, anthrax vaccine is given in combination with antibiotic medicine. Be sure to use the antibiotic for the full prescribed length of time, even if you feel fine.

The anthrax vaccine is given in a series of shots. An annual booster shot is also recommended every year during possible exposure to anthrax. Follow your doctor's instructions or the booster schedule recommended by the health department of the state where you live.

What happens if I miss a dose?

Contact your doctor if you will miss a booster dose or if you get behind schedule. The next dose should be given as soon as possible. There is no need to start over.

Be sure you receive all recommended doses of this vaccine. You may not be fully protected against disease if you do not receive the full series.

What happens if I overdose?

An overdose of this vaccine is unlikely to occur.

What should I avoid before or after receiving anthrax vaccine?

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

Anthrax vaccine side effects

Keep track of any and all side effects you have after receiving this vaccine. When you receive a booster dose, you will need to tell the doctor if the previous shot caused any side effects.

Becoming infected with anthrax is much more dangerous to your health than receiving this vaccine. However, like any medicine, this vaccine can cause side effects but the risk of serious side effects is extremely low.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Anthrax vaccine may cause serious side effects. Call your doctor at once if you have:

  • a light-headed feeling, like you might pass out;

  • fever, chills, body aches, nausea, flu symptoms; or

  • severe swelling or a hard lump where the shot was given.

Common side effects include:

  • redness, swelling, or tenderness where the shot was given;

  • trouble moving the injected arm;

  • muscle pain;

  • fainting;

  • feeling tired; or

  • headache.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report vaccine side effects to the US Department of Health and Human Services at 1 800 822 7967.

Anthrax vaccine dosing information

Usual Adult Dose for Anthrax Prophylaxis:

Pre-Exposure Prophylaxis:
Primary series: 0.5 mL intramuscularly at 0, 1, and 6 months
Booster series: 0.5 mL intramuscularly 6 and 12 months after primary series and at 12-month intervals thereafter

Pre-Exposure Prophylaxis in patients at risk of hematoma from intramuscular injection:
Primary series: 0.5 mL subcutaneously at 0, 2, and 4 weeks and 6 months
Booster series: 0.5 mL subcutaneously 6 and 12 months after primary series and at 12-month intervals thereafter

Post-Exposure Prophylaxis:
Primary series: 0.5 mL subcutaneously at 0, 2, and 4 weeks post-exposure combined with antimicrobial therapy

-Efficacy for post-exposure prophylaxis is based solely on animal models of inhalation anthrax.
-The optimal catch up schedule for missed or delayed booster doses is unknown.

-Active immunization of patients aged 18 to 65 for pre-exposure prophylaxis in those at high risk of exposure
-Active immunization of patients aged 18 to 65 for post-exposure prophylaxis after suspected or confirmed Bacillus anthracis exposure, administered in conjunction with recommended antibacterials

What other drugs will affect anthrax vaccine?

Before receiving this vaccine, tell your doctor about all other vaccines you have recently received.

Also, tell your doctor if you have recently received drugs or treatments that can weaken the immune system, including:

If you are using any of these medications, you may not be able to receive the vaccine, or may need to wait until the other treatments are finished.

This list is not complete. Other drugs may affect this vaccine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.