Vitamin A toxicity
Hypervitaminosis A is a disorder in which there is too much vitamin A in the body.
Vitamin A is a fat-soluble vitamin that is stored in the liver. Many foods contain vitamin A, including:
Some dietary supplements also contain vitamin A.
Supplements are the most common cause of vitamin A toxicity. It tends not to occur just from eating vitamin A-rich foods.
Too much vitamin A can make you sick. Taking large doses during pregnancy can cause birth defects.
Symptoms may include:
These tests may be done if a high vitamin A level is suspected:
Treatment involves simply stopping supplements (or in rare cases, foods) that contain vitamin A.
Most people fully recover.
Complications can include:
Taking too much vitamin A during pregnancy may cause birth defects. Talk to your health care provider about eating a proper diet while you are pregnant.
You should call your provider:
How much vitamin A you need depends on your age and sex. Other factors, such as pregnancy and your overall health, are also important. Ask your provider what amount is best for you.
To avoid hypervitaminosis A, don't take more than the recommended daily allowance of this vitamin.
Some people take vitamin A and beta carotene supplements in the belief it will help prevent cancer. This may lead to chronic hypervitaminosis A if people take more than is recommended.
Institute of Medicine (US) Panel on Micronutrients. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington, DC: National Academies Press; 2001. PMID: 25057538 pubmed.ncbi.nlm.nih.gov/25057538/.
James WD, Elston DM, Treat JR, Rosenbach MA, Neuhaus IM. Nutritional diseases. In: James WD, Elston DM, Treat JR, Rosenbach MA, Neuhaus IM, eds. Andrews' Diseases of the Skin. 13th ed. Philadelphia, PA: Elsevier; 2020:chap 22.
Mason JB, Booth SL. Vitamins, trace minerals, and other micronutrients. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 205.
Roberts NB, Taylor A, Sodi R. Vitamins and trace elements. In: Rifai N, ed. Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. 6th ed. Philadelphia, PA: Elsevier; 2018:chap 37.
Ross AC. Vitamin A deficiencies and excess. In: Kliegman RM, St. Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM, eds. Nelson Textbook of Pediatrics. 21st ed. Philadelphia, PA: Elsevier; 2020:chap 61.BACK TO TOP
Review Date: 1/26/2020
Reviewed By: Brent Wisse, MD, board certified in Metabolism/Endocrinology, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- 2022 A.D.A.M., a business unit of Ebix, Inc. Any duplication or distribution of the information contained herein is strictly prohibited.