Vitamin A toxicity
(Redirected from Hypervitaminosis A)
- Majority due to chronic ingestion of synthetic vitamin A
- Toxic dose is approximately 10x higher than Recommended Dietary Allowance (RDA), totaling ~50,000 units
- Provitamin A (beta-carotene) ingestion very unlikely to cause toxicity
- Carotenemia common in children eating leafy green vegetables or carrots, with spontaneous resolution after cessation of foods
- Single dose >660,000 IU (>200,000 micrograms)
- Symptoms include nausea/vomiting, vertigo, blurry vision
- Greater than x10 amount of RDA
- Symptoms include: skin irritation, alopecia arthralgias/bone pain, hyperlipidemia, hepatotoxicity, ataxia, visual impairment,headache elevated ICP
Retinoic acid in 1st trimester
- Very teratogenic
- Spontaneous abortions and fetal malformation
- Vitamin A in pregnancy safe upper limit 10,000IU
- Vitamin A stored in liver-circulating vitamin A will likely not reflect vitamin A stores
- Measurement of serum retinyl esters more accurate in fasting state
- Discontinue high vitamin A intake
- Most fully recover
- Vitamin E supplementation
- Manage complications of liver failure
- Liver transplant may necessary in severe toxicity w/fulminant liver failure
- Consider tox or poison control consult
- Dependant on severity
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