Vitamin A (Retinol)
Indications
Vitamin A (Retinol) is used for:
Vitamin A deficiency, Night blindness, Xerophthalmia
Adult Dose
Oral
Vitamin A deficiency
Adult: For severe deficiency with corneal changes: 500,000 units daily for 3 days, followed by 50,000 units daily for 2 wk and then 10,000-20,000 units daily for 2 mth as follow-up therapy. For cases with corneal changes: 10,000-25,000 units daily until clinical improvement occurs (usually 1-2 wk).
Child Dose
Oral
Vitamin A deficiency
Child: In children with xerophthalmia: 5000 units/kg daily for 5 days or until recovery occurs.
Renal Dose
Administration
Should be taken with food.
Contra Indications
Hypervitaminosis A; pregnancy (dose exceeding RDA).
Precautions
Cholestatic jaundice; fat-malabsorption conditions. Monitor patients closely for toxicity. Liver impairment and children.
Pregnancy-Lactation
Pregnancy Category: A (oral); C (doses exceeding RDA); X (>6,000 units/day administered parenterally)
Lactation: Distributed into milk; safe at RDA levels
Interactions
Decreased absorption with neomycin. Increased risk of hypervitaminosis A with synthetic retinoids eg, acitretin, isotretinoin and tretinoin. Increased risk of toxicity when used with alcohol.
Side Effects
Side effects of Vitamin A (Retinol) :
Hypervitaminosis A characterised by fatigue, irritability, anorexia, weight loss, vomiting and other GI disturbances, low-grade fever, hepatosplenomegaly, skin changes, alopoecia, dry hair, cracking and bleeding lips, SC swelling, nocturia, pains in bones and joints.
Mode of Action
Vitamin A plays an essential role in the function of retina and is essential for growh and differentiation of epithelial tissue.