Allergic to vitamin B12

If you are allergic to cobalt, it may be caused by vitamin B12 (cobalamin). That’s because the cobalamin molecule contains a cobalt atom.

Cobalt is a versatile mineral. It’s found in rechargeable batteries, car airbags, steel-belted tires, and magnets. It imparts a unique blue hue to the glass. It is used as a blue pigment in cosmetics, paints and inks.

If you are allergic to cobalt, high doses of B12 can cause contact dermatitis. This article explores the symptoms and causes of this allergy, as well as how to diagnose and treat it.

emergency symptoms

In rare cases, intramuscular injection of vitamin B12 may cause a life-threatening allergic reaction. Anaphylaxis is always a medical emergency.

Symptoms may include:

  • itching
  • measles
  • shortness of breath
  • respite
  • Vomit
  • diarrhea

Get medical help right away for these symptoms.


Contact dermatitis is usually not life-threatening. Rare vitamin B12 can be allergic. Even so, it is rarely reported.

There are two types of contact dermatitis: irritant and allergic.

Irritants can cause irritant contact dermatitis in anyone. Allergic contact dermatitis is only possible if you are allergic to the substance.

Contact dermatitis rashes are:

  • redness, itching, burning and/or pain
  • Sometimes blistering or oozing
  • Caused by direct contact with the substance in question

Your skin may be dry, cracked, inflamed, and soft to the touch. This reaction can happen anywhere on your body.

How do allergies work?


In the United States, contact dermatitis results in millions of doctor visits each year. People of all ages are affected. Studies show that 20% of people are affected by this condition.

Women are more frequent than men. Teens and middle-aged people seem to get it more easily than other age groups.


Vitamin B12 can trigger cobalt allergy. It causes contact dermatitis, a painful red rash. About one in five Americans suffers from contact dermatitis.


Vitamin B12 plays an important role in your body. It helps in the formation of blood cells. It is essential for a healthy nervous system.

B12 is present in many dietary sources. Most multivitamins also contain large amounts of vitamins. Despite this, B12 deficiency is still common.

Vitamin B12 deficiency

According to the National Institutes of Health, 6% of people under the age of 60 are B12 deficient. Among those over the age of 60, the percentage is closer to 20%.

Your body must absorb vitamins in order to use them. With vitamin B12, the process is complicated. It includes various steps that are prone to defects.

This can lead to poor absorption of vitamin B12 in the small intestine. This can lead to defects.

To boost your levels, you may need to take a vitamin B12 supplement by mouth or by injection.

Understanding Vitamin D Deficiency

Cobalt and Vitamin B12 Allergy

Cobalt allergy most commonly occurs in people exposed to it in eye makeup, tattoos, or industrial products.

Once you are allergic to cobalt, you can develop allergic contact dermatitis whenever you are exposed.

If you are deficient in B12, a cobalt allergy can make it difficult to control. Discuss with your healthcare provider how much B12 is safe for you.


Most cobalt exposures come from cosmetic and industrial uses.

B12 deficiency is common. Cobalt allergies make them difficult to treat.


Cobalt allergy was diagnosed by a patch test. This includes placing a coin-sized cobalt patch on your back for about 48 hours.

Record your response after 48 hours, then again after a day or two. The test is positive if you develop blisters, redness, and/or mild swelling in the area.

Blood and skin tests for allergic reactions


Rashes from allergic contact dermatitis can be treated with topical or systemic corticosteroids. But the best treatment for a cobalt allergy is to avoid high doses of vitamin B12.

If you are deficient in B12, you should only take the minimum amount needed to raise your levels to normal.


High doses of vitamin B12 can trigger cobalt allergy. This can lead to a red, painful rash called contact dermatitis.

Most cobalt exposures come from cosmetics, industrial uses, and B12 supplements.

Cobalt allergy is diagnosed with a patch test. Contact dermatitis is treated with steroids. Avoiding large amounts of B12 can help control the condition.

VigorTip words

If you know you are allergic to cobalt, please speak to any healthcare provider who recommends B12 supplementation. They can work with you to find a safe dose.

If you develop contact dermatitis or other allergic symptoms after possible exposure to cobalt, discuss allergy testing with your healthcare provider.

Get emergency medical help whenever you or someone else has trouble breathing.

Frequently Asked Questions

  • Are you allergic to vitamin B12?

    Yes, people allergic to cobalt can have an allergic reaction to vitamin B12 (also known as cobalamin). Cobalamin contains cobalt atoms. However, this allergy is rare.

  • Can too much vitamin B12 cause a rash or itchy skin?

    Yes, taking large amounts of vitamin 12 can cause skin reactions in people who are sensitive to cobalt. Symptoms include an itchy rash.

  • How do you know if you are allergic to B12 or cobalt?

    A cobalt allergy usually begins when you come into contact with cobalt in eye makeup, tattoos, or industrial products. It causes an itchy red scaly rash.

    Vitamin B12 sensitivity may manifest as a rash after taking the supplement. A severe allergic reaction called anaphylaxis can occur after taking large amounts of vitamin B12 by mouth or by injection.