Retinol esters have been used as markers
Retinyl esters can be distinguished from retinol in serum and other tissues and quantified with the use of methods such as high-performance liquid chromatography.Elevated amounts of retinyl ester (i.e., >10% of total circulating vitamin A) in the fasting state have been used as markers for chronic hypervitaminosis A in humans and monkeys. This increased retinyl ester may be due to decreased hepatic uptake of vitamin A and the leaking of esters into the bloodstream from saturated hepatic stellate cells. Prevention
Hypervitaminosis A can be prevented by not ingesting more than the US Institute of Medicine Daily Tolerable Upper Level of intake for Vitamin A. This level is for synthetic and natural retinol ester forms of vitamin A. Carotene forms from dietary sources are not toxic. Possible pregnancy, liver disease, high alcohol consumption, and smoking are indications for close monitoring and limitation of vitamin A administration. Daily tolerable upper level
Treatment
Stopping high vitamin A intake is the standard treatment. Most people fully recover. Phosphatidylcholine (in the form of PPC or DLPC), the substrate for Lecithin retinol acyltransferase, which converts retinol into Retinyl esters (the storage forms of vitamin A). Vitamin E may alleviate hypervitaminosis A.
Liver transplantation may be a valid option if no improvement occurs.If liver damage has progressed into fibrosis, synthesizing capacity is compromised and supplementation can replenish PC. However, recovery is dependent on removing the causative agent: halting high Vitamin A intake.
Although not considered part of standard treatment, they might be of some benefit to humans. Vitamin E appears to be an effective treatment in rabbits, and prevents side effects in chicks
Taurine significantly reduces toxic effects in rats. Retinoids can be conjugated by taurine and other substances. Significant amounts of retinotaurine are excreted in the bile, and this retinol conjugate is thought to be an excretory form, as it has little biological activity. Red yeast rice ("cholestin") – significantly reduces toxic effects in rats. Vitamin K prevents hypoprothrombinemia in rats and can sometimes control the increase in plasma/cell ratios of vitamin A. See also
Vitamin poisoning
Far Eastern Party
Retinoic acid syndrome
Piblokto

References
External links

Facts about Vitamin A and Carotenoids, from the National Institutes of Healths Office of Dietary Supplements.