Cobalt is a mineral with many uses. It’s in rechargeable batteries, automotive airbags, steel-belted tires, and magnets. It gives a distinctive blue tint to glass. It’s used as a blue pigment in cosmetics, paints, and inks.
If you’re allergic to cobalt, high B12 doses can cause contact dermatitis. This article explores the symptoms and causes of this allergy plus how it’s diagnosed and treated.
Symptoms
Contact dermatitis isn’t usually life-threatening. The rare vitamin B12 allergy can be. Even so, it’s rarely reported.
Symptoms may include:
Itching Hives Shortness of breath Wheezing Vomiting Diarrhea
Get immediate medical help for these symptoms.
Contact dermatitis comes in two types: irritant and allergic.
Irritants can cause irritant contact dermatitis in anyone. Allergic contact dermatitis is only possible if you’re allergic to the substance.
A contact dermatitis rash is:
Red, itchy, burning, and/or painfulSometimes blistering or oozingCaused by direct contact with the problem substance
Your skin may be dry, cracked, inflamed, and tender to the touch. The reaction can happen anywhere on your body.
Prevalence
Contact dermatitis leads to millions of doctor visits each year in the United States. People of all ages are affected. Research suggests 20% of all people are affected by this condition.
Females have it slightly more often than males. Teenagers and middle-aged adults seem to get it more than other age groups.
Causes
Vitamin B12 plays important roles in your body. It helps blood cells form. And it’s critical for a healthy nervous system.
B12 is available in many dietary sources. Most multivitamins contain plenty, as well. Still, B12 deficiencies are common.
Vitamin B12 Deficiency
The National Institutes of Health says 6% of people under age 60 have a B12 deficiency. Among people over 60, it’s closer to 20%.
Your body has to absorb vitamins in order to use them. With vitamin B12, the process is complicated. It includes various steps that are prone to defects.
That can lead to poor absorption of vitamin B12 from the small intestine. This causes a deficiency.
To raise your levels, you may need oral or injectable vitamin B12 supplements.
Cobalt and Vitamin B12 Allergy
Cobalt allergies most often develop in people exposed to it in eye makeup, tattoos, or industrial products.
Once you’re sensitized to cobalt, you’ll develop allergic contact dermatitis whenever you’re exposed.
If you have a B12 deficiency, a cobalt allergy can make it hard to manage. Talk to your healthcare provider about how much B12 is safe for you.
Diagnosis
A cobalt allergy is diagnosed with a patch test. This involves placing a dime-sized cobalt-laden patch on your back for about 48 hours.
B12 deficiencies are common. A cobalt allergy makes them hard to treat.
Your reaction is noted after 48 hours, then again a day or two later. The test is positive if you have blisters, redness, and/or mild swelling at the site.
Treatment
The rash from allergic contact dermatitis can be treated with topical or systemic corticosteroids. But the best treatment for a cobalt allergy is avoiding large doses of vitamin B12.
If you have a B12 deficiency, you should only take the minimum amount needed to raise your levels to normal.
Summary
Large doses of vitamin B12 can trigger a cobalt allergy. That may cause a red, painful rash called contact dermatitis.
Most cobalt exposure is from makeup, industrial uses, and B12 supplements.
Cobalt allergies are diagnosed with a patch test. Contact dermatitis is treated with steroids. Avoiding large amounts of B12 helps manage the condition.
A Word From Verywell
If you know you have a cobalt allergy, bring that up with any healthcare provider who suggests a B12 supplement. They can work with you to find a safe dosage.
If you have contact dermatitis or other allergy symptoms after a possible cobalt exposure, talk to your healthcare provider about allergy testing.
Any time you or someone else has trouble breathing, get emergency medical help.
A vitamin B12 sensitivity can appear as a rash after you take a supplement. A severe allergic reaction, known as anaphylaxis, can occur after taking large amounts of vitamin B12 orally or as an injection.
