This doesn't exactly answer your question because 1) I didn't take HIGH dose vitamin A and 2) I really can't speak to how risky it is. (Though I wouldn't do it myself, personally. I just feel like mega-dosing always comes with a downside.)

That said, I did see a dramatic improvement in the clarity and texture of my skin since taking a dose of fermented cod liver oil/butter oil blend. Nothing huge, just 1/2 tsp a day. My acne wasn't extreme (though it was pretty bad when I was younger), but I had breakouts, lots of redness, and a rough texture that never seemed to go away now matter how much (or how little) I exfoliated. It took about a month to see a difference, but when I did it was remarkable and it hasn't gone away, even when I have stopped the FCLO/BO for weeks at a time because I ran out or something.

I have seen similar improvements with topical retinols, but those have always had a strange hook effect with me--they will help for awhile (a month or two) and then my skin seems to adapt to them and go back to its original state. I have not yet experienced this with the FCLO/BO and it has been about 6-7 months.

My mom is a dermatologist and yes it definitely works. If you have ever heard of the drug Accutane, that is all it is- high doses of vitamin A. The side effects could be large with this drug but mostly because the doses were like 5x what you are suggesting to take. Either way I take cod liver oil and eat lots of sweet potatoes and I don't break out as badly as I used to in a long time!

someone on acne.org took sth like 300 000 IU daily, he might have posted some blood tests....

Hm , i'm not a proffesional of what , but here's my take on your question .I feel that nutrients or whatever from whole foods should be enough and there is not really a need to take supplements(i maybe wrong and maybe you meant that you take high dosages of vitamin A from whole foods.) . Our body has many ways to remove toxic or substance deemed harmful to us in many ways such as ,our standard excretion of waste or whatsoever , it can also come in the form of a breakout , basically i feel that if you had a sound diet and healthy lifestyle ( frequent exercise and adequate sleep ) breakouts will eventually stop . *NOTE * i am just giving my opinions and i'm not trying to prove anything , this is just what i feel and SKIP OILY AND DEEP FRIED FOODS :)

although i did not take the high doses of straight vitamin A, i have been on Accutane which i believe is a derivative of very high doses of Vitamin A so works on the same principle. i had to be closely monitored by a physician and blood/liver enzyme tests once a month. Being female of child bearing years i had to go on the pill (boooo) as high doses of vitamin A/Accutane is known to have teratogenous effects on the fetus. Very scary. Drug also linked to suicidal thoughts/depression, etc; unsure if vitamin A would effect you the same way. Being fat soluble vitamin it will be stored in your tissue a while.....as was the acccutane. it was very effective for acne however other undesireable side effects. I wouldn't do it on your own.....the vitamin A. goodluck!

Try cutting out dairy. I've personally seen that end acne and I've read it in numerous places too. Plus it's much simpler and less risky than pounding a bunch of vitamins!

500,000 IU Per Day

Don't try this at home!

Abstract

Oral vitamin A (retinol) is generally not considered useful in the treatment of acne vulgaris. We conducted a study which showed that retinol was indeed ineffective at the usual doses of 50,000 to 100,000 IU daily. Retinol was highly efficacious in doses of 300,000 units for women and 400,000 to 500,000 units for men, toxicity was slight and limited mainly to skin (xerosis) and mucous membranes (cheilitis). The danger of hypervitaminosis A in this dosage range has been exaggerated. Retinol is a valuable drug for treating stubborn, severely inflammatory acne vulgaris. It is administered until the disease is brought under control, usually within three to four months. Then the dosage is progressively reduced relying on conventional drugs to keep the disease in abeyance.

Link

did the accutane thing to get rid of cystic acne on the face. it worked perfectly. a random pimple will surface every few months or so but never a cystic one. anyone who has had cystic acne knows it sucks. while on accutane, i wasnt allowed to take any extra supplements and was blood tested every month. i followed the orders strictly and for 6 months did not supplement with anything. my brother continued taking protein powders and a few other supplements and he still has issues with acne because of it. i didnt experience any side effects except that my skin was drier than normal to the point i had to lotion my hands a few times. my lips werent horribly chapped but did dry out more frequently. the weirdest side effect was the loss of a cuticle on my finger nails which resulted in NEVER HAVING A HANGNAIL! that was nice. when i took accutane, i was warned about suicidal thoughts but i figured those stemmed from people who were already having those thoughts due to the acne and then having extreme skin drying side effects. definitely do it at your own risk and understand that the safest way to do it would be through a doctor so your blood and liver can be monitored.

Lol hahahaha vitamin A is just wah wah!!!