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Hypervitaminosis A

Hypervitaminosis A is having too much vitamin A in the body.


There are two types of hypervitaminosis A:

  • Acute -- when the vitamin A level in the body suddenly increases over a short period of time
  • Chronic -- when too much vitamin A is present in the body over a longer period of time


  • Abnormal softening of the skull bone (craniotabes -- in infants and children)
  • Blurred vision
  • Bone pain or swelling
  • Bulging fontanelle (the soft spot in an infant's skull)
  • Changes in consciousness
  • Decreased appetite
  • Dizziness
  • Double vision (in young children)
  • Drowsiness
  • Hair changes, such as hair loss and oily hair
  • Headache
  • Increased pressure in the skull
  • Irritability
  • Liver damage
  • Nausea
  • Poor weight gain (in infants and children)
  • Skin changes, such as cracking at corners of the mouth, higher sensitivity to sunlight, oily skin, peeling, itching, and yellow color to the skin
  • Vision changes
  • Vomiting

Exams and Tests

  • Bone x-rays
  • Blood calcium test
  • Cholesterol test
  • Liver function test
  • Blood test to check vitamin A levels


Treatment involves simply stopping supplements (or rarely, foods) that contain vitamin A.

Outlook (Prognosis)

Most people fully recover.

Possible Complications

  • Excessively high calcium levels
  • Failure to thrive in infants
  • Kidney damage due to high calcium
  • Liver damage

Taking too much vitamin A during pregnancy may cause abnormal development in the growing baby. Talk to your health care provider about eating a proper diet while you are pregnant.

When to Contact a Medical Professional

Call your health care provider if you think that you or your child may have taken too much vitamin A, or you have symptoms of excess vitamin A.


To avoid hypervitaminosis A, avoid taking more than the recommended daily allowance of this vitamin. Recent emphasis on vitamin A and beta carotene as anticancer vitamins may contribute to chronic hypervitaminosis A, if people take more than is recommended.

Alternative Names

Vitamin A toxicity


Mason JB. Vitamins, trace minerals, and other micronutrients. In: Goldman L, Schafer AI, eds.Goldman's Cecil Medicine

Zile MH. Vitamin A deficiencies and excess. In: Kliegman RM, Stanton BF, St. Geme JW III, Schor NF, Behrman RE, eds.Nelson Textbook of Pediatrics

Update Date 5/10/2014

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