Vitamin B Complex

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VEYE-tah-min B KOM-plex - Pronunciation guide

Brand Names

  • Super B Complex
  • Vita-Jec® B-Complex 
  • Vitamin B Complex 150 Injection
  • V.A.L.® Syrup
  • Vitamin B Complex 150
  • B ComplexVET


Rx symbolVitamin B complex is used to prevent and treat vitamin B deficiencies in horses. Injectable prescription B vitamin complex usually contains thiamine, riboflavin, pyridoxine, niacinamide, d-panthenol, and cyanocobalamin.

The B complex vitamins are water-soluble and reserves are not stored in the body, so daily intake is required. Good quality pasture contains high levels of these vitamins, but cereal grains that make up concentrated ‘hard’ feeds have a low or imbalanced content of natural vitamins.

The vitamin B complex, specifically thiamin (B-1) and B-12, is responsible for the metabolism of the horse’s nutrients, such as fats, proteins, and carbohydrates.

Other B vitamins that assist with the nutrient metabolism are riboflavin (B-2) and pantothenic acid (B-5). Riboflavin is required for the health of the mucous membranes in the digestive tract. Panthothenic acid assists some of the glands and hormones that aid metabolism of nutrients.

If a horse is experiencing vitamin B deficiencies, an injection of the vitamin B complex may help by boosting the metabolism and allowing the horse’s body to use the food it is eating. But if a horse is healthy and not experiencing any deficiency, then an injection of vitamin B would most likely not do much for the horse.

In fact, if a horse is not deficient, an injection of vitamin B complex may be a waste of money because vitamin B is water soluble and any excess is excreted in the urine almost immediately.


Vitamin B complex is used in the prevention and treatment of conditions associated with vitamin B deficiency. It is most commonly used in animals that are not eating adequately, or have a debilitating disease, liver condition, or long convalescence after major surgery.

B complex vitamins are involved in energy production, digestive and liver function, and blood production. Hard working horses may benefit from supplementary B complex vitamins.

Dosage and Administration

Prescription medicationVitamin B Complex
Method Dosage
(click row for calculator)
Concentration Period Duration
Oral (syrup)1 1-2 tbs   Each day As needed
Oral (capsules)2 4-8 capsules   Each day As needed
Intramuscular injection3 10-20 ml See package 1 or 2 times a week As needed
Intravenous, Intramuscular or Subcutaneous injection3 1-5 ml/100lb 150 mg/ml 1 or 2 times a week As needed


  • 1V.A.L. Syrup
  • 2B ComplexVet
  • 3Parenteral administration of thiamine has resulted in anaphylactic shock. Administer slowly and with caution in doses over 1/3 mL (50 mg Thiamine).
  • Federal law restricts this drug to use by or on the order of a licensed veterinarian..
  • Extra-label use of drugs in treating animals is allowable only by licensed veterinarians within the context of a valid veterinarian-client-patient relationship, and does not include drug use in treating animals by the layman (except under the supervision of a licensed veterinarian).
  • The duration of administration depends on the condition being treated, response to the medication and the development of any adverse effects. Be certain to complete the prescription unless specifically directed by your veterinarian. Even if your equine appears to feel better, the entire treatment plan should be completed to prevent relapse.
  • This medication may be available in forms and concentrations not noted in the above table. Always check the label and literature provided with the medication about the form and concentration and DO NOT USE the calculator if the information differs.
  • Calculator is for educational purposes only. Follow your veterinarian's instructions regarding use of this, or any medication.

Following the directions of a veterinarian is very important.

Vitamin B complex can be given in oral or injectable form. It is best to give a daily feed supplement (e.g. powder, paste, or liquid) and administer extra by injection where necessary, usually prior to or immediately after periods of stress, racing, or hard work.

Administer injections of vitamin B complex with caution and keep treated horse under close observation in case of allergic reaction.

Side Effects

Although side effects are uncommon, allergic reaction to the medication may occur. Signs may include facial swelling, hives, scratching, sudden onset of diarrhea, shock, seizures, pale gums, and, in severe cases, coma. Discuss the potential for side effects in your horse with your veterinarian.


Vitamin B complex is not for use in horses that are hypersensitive to thiamine or any of the other ingredients. Although some vitamin B complex injectables caution about intravenous use, other products indicate on the package that they may be given intravenously. Always consult with your veterinarian before administration. Anaphylactic reactions to parenteral thiamine HCl have been reported.


None reported.


Studies have shown a very low order of toxicity if vitamin B complex is used according to instructions.


Vita-Jec Vitamin B Complex InjectionVita-Jec Vitamin B Complex Injection

Vitamin B Complex InjectionVitamin B Complex Injection



About the Author

EquiMed Staff

EquiMed staff writers team up to provide articles that require periodic updates based on evolving methods of equine healthcare. Compendia articles, core healthcare topics and more are written and updated as a group effort. Our review process includes an important veterinarian review, helping to assure the content is consistent with the latest understanding from a medical professional.