BotVax B for Horses

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What Is BotVax B Used for in Horses?

BotVax B is the only USDA-approved injectable vaccination used to prevent botulism (caused by Clostridium botulinum Type B) in healthy horses.  

While there are several types of C. botulinum (A-F), Type B is the culprit of forage poisoning, shaker foal syndrome, and "traditional" or wound botulism.  

How BotVax B Works in Horses

The BotVax B vaccine is a monovalent toxoid vaccine. This means that the harmful, disease-causing toxin that’s created by Clostridium botulinum has been inactivated and used as an ingredient.  

This will not cause active disease, but it will still stimulate the immune system to create a response for later protection against possible exposure to the live disease-causing bacteria in the environment.  

C. botulinum Type B is the result of ingested toxins in contaminated feed, like moldy hay, spoiled silage or haylage, or decaying plant matter; or it enters the body through a wound from the environment. The bacteria then spread throughout the body and release the botulinum toxin, which is responsible for a wide range of clinical symptoms.  

While this toxin can affect all mammals, horses are one of the most susceptible species. 

How To Give BotVax B to Horses

Follow the directions on the drug label or as provided by your veterinarian.  

Because this is a risk-based vaccination, it may be given depending on your geographical location or risks for your individual horse. Always discuss vaccination protocols with your veterinarian.  

This vaccine is labeled for adult horses, pregnant mares, and foals older than 2 weeks. Botulism is often linked to geographical locations (Kentucky and the mid-Atlantic states) and can affect both adult horses and foals. 

This vaccination is given in a three-dose series for the initial vaccination, then as a yearly booster for continuous protection. For the initial inoculations, the doses are given one month apart. 

Shake well before use and do not mix with other products.  

To administer a vaccine sanitized: 

• Vaccinate using a clean, new needle. Each animal should be vaccinated using a clean, new needle—typically a 20-gauge, 1.5-inch needle. Pull up 2 ml of vaccine from the vial. 

• Administer within the intramuscular (IM) administration site. This is located below the nuchal ligament, above the cervical vertebrae, and in front of the shoulder blade.  

• Insert the needle straight in, perpendicular to the skin. Insert all the way to the hub of the needle. Pull back slightly on the plunger to evaluate for any blood in the needle. If blood is visible, either redirect the needle or select a new injection site. 

• Push the plunger. If no blood is seen, proceed to push the plunger to administer the vaccine. 

Missed a Dose? 

Speak with your veterinarian about what to do if you forget to give a dose of BotVax B to your horse, especially during the initial vaccine series.  

Generally, your vet may instruct you to give it when you remember and then delay the next vaccine to stay on schedule.  

Do not give extra or double doses. 

Possible Side Effects of BotVax B for Horses

If you notice any of the following side effects, please contact your veterinarian immediately: 

• Temporary decreased appetite 

• Colicky symptoms 

• Anaphylactic reaction (collapse, rapid breathing, hives) 

Transitory local reactions at the injection site may occur, such as heat and minor swelling. Use of epinephrine is antidotal for anaphylactic reactions. 

Human Side Effects 

Due to possible side effects, humans should never use medicine dispensed for their horse and horses should not be given any medicine dispensed for a human’s use. 

If you come into contact with BotVax B, the vaccination may cause skin, eye, or respiratory irritation. Ingestion may cause vomiting and nausea.  

Pregnant women should avoid handling or wear gloves, and all humans should wash hands after use. 

If you accidentally ingest an animal medication, seek medical attention immediately in person and call Poison Control at 800-222-1222. 

When To Call Your Vet 

Call your veterinarian if you see any of the following: 

• Severe side effects (above) 

• You see or suspect an overdose 

• If you have additional questions or concerns about the use of BotVax B 

BotVax B Overdose Concerns in Horses

Ask your veterinarian about any concerns if you accidentally inject too much vaccine into your horse. 

How To Store BotVax B for Horses

Keep the following storage tips in mind for this medication: 

• Store unopened vials at 35–45 F (2–8 C).  

• Do not freeze the vials.  

• The manufacturer states that the entire contents of the vial be used when first opened and that partial/opened vials should not be stored.