| An intake of retinoids, much more than required,
results in the toxic syndrome known as hypervitaminosis A. Causes
Most frequently, high intakes in children are the result of overzealous prophylactic
vitamin therapy. Toxicity in adults has resulted from extended self -medication, food
fads, or from the use of retinoids for the therapy of acne or skin lesions.
Signs and symptoms
Early signs and symptoms of chronic retinoid intoxication include dry and pruritic
(itchy) skin, skin desquamation, dermatitis, disturbed hair growth, fissure of the lips,
pain and tenderness of the bone, headache, anorexia, edema, fatigue, irritability and
haemmorhage.
In infants, increased intracranial pressure, a bulging fontanel and vomiting are seen
early.
The case of acute poisoning include drowsiness, irritability or irresistible desire to
sleep, severe headache due to intracranial pressure, dizziness, hepatomegaly, vomiting and
after 24 hours, generalised peeling of the skin.
Prevention and treatment
Concentrations of retinol in plasma more than 100 m g /dl (3.5 m m) usually are
diagnostic of hypervitaminosis A. Treatment consists of withdrawal of the retinoid. Most
signs and symptoms disappear within a week, but the desquamation and hyperostosis* remain
evident for several months after clinical recovery, and in rare instances the bone
malformations may be permanent.
* Enlargement of the bone
Vitamin A
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