Review Note

Vitamin A (Retinol, Retinoic Acid)
• Use: {{c1::oral supplement; vitamin A also used in topical creams to reduce fine wrinkles and treat acne}}

Recommended Daily Dosing (Oral):
• 900 micrograms (mcg) for adult men, 700 mcg for adult women

Safety:
• Excess vitamin A {{c2::during pregnancy linked to birth defects}}
• >200,000 mcg  nausea, vomiting, vertigo, blurry vision
• >10,000 mcg per day long term --> bone thinning, liver damage, skin irritation, joint/bone pain, birth defects

Drug Interactions:
• Anticoagulants: {{c3::increase risk of bleeding}}
• Avoid {{c4::concomitant oral retinoids (isotretinoin for acne)}} --> high vitamin A blood concentration

Vitamin A deficiency --> anemia, dry eyes (rare in U.S.A.)