Rashes Caused by Prenatal Vitamins

Rashes caused by prenatal vitamins are most likely the result of an allergic reaction and need to be assessed by a medical doctor.

Drugs.com warns that hives that develop after taking prenatal vitamins may indicate a severe allergic reaction.

Other rashes that can develop from an allergy to prenatal vitamins include general itching and eczema. Prenatal vitamins are an important aspect of prenatal care. Any adverse reactions after taking prenatal vitamins needs to be discussed with your healthcare provider for the best preventative and treatment options.

Prenatal Drug Allergy

Prenatal drugs are a multi-vitamin specifically formulated to provide the appropriate nutrition to women who may become pregnant, are pregnant or are breast feeding. If you’re allergic to one or more of the ingredients in the multi-vitamin, your immune system will react by defending the body.

The immune system mistakes an ingredient in the vitamin as dangerous and develops immunoglobulin E, or IgE, antibodies that work to specifically fight against the allergen, according to MedlinePlus. Skin rashes are common with a vitamin allergy.

Allergic Skin Reactions

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Allergic skin reactions from prenatal vitamins result from increased levels of histamine in the skin. When your body creates IgE antibodies, mast cells release higher levels of histamine to protect the body.

Histamine is a naturally occurring chemical in the body that prevents infection, but in larger quantities, it can cause inflammation.

Hives, eczema and general itching may be a result of increased histamine levels. These skin rashes can appear anywhere on the body, causing swelling, redness and itching, according to the American Academy of Allergy, Asthma & Immunology.


Your doctor may want to run a series of tests to determine which ingredient is causing the allergic reaction rash. You may be allergic to a specific vitamin or you may be allergic to an ingredient, such as whey, gluten or soy.

Allergy tests use small amounts of the suspected allergens to determine if your body creates IgE antibodies when introduced. Skin tests will expose your skin to a specific substance in the prenatal vitamin to observe if the skin becomes inflamed and irritated.

Fish Allergy Consideration

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Many prenatal vitamin regimens include fish oil supplements.

If you’re allergic to fish, you may experience an allergic reaction while taking fish oil supplements, states MedlinePlus. A fish allergy commonly causes skin reactions, facial swelling and tingling in the lips, tongue or mouth.