Say you come across a patient in the throes of scurvy: bleeding gums, loose teeth, pain all over, all sorts of malfunctioning organs and say, “Poor fella, how about you drink this jug of fortified orange juice” and watch in satisfaction as he chugs down the equivalent of 10x or 20x his recommended daily value for Vitamin C.
Would giving such a Vitamin-C-deprived person a huge sudden blast like that be harmful to him, and if so, how specifically?
If this person has loose teeth and bleeding gums, a big jug of OJ is going to
sting and burn like all get out.
Too much vitamin C: Is it harmful? - Mayo Clinic
This link suggests that mega doses of Vit C might be unpleasant eventually,
but not toxic. Our bodies are designed to pee out any excess water soluble
and Vit C is one of those.
A better question might be: why are you asking? 
To avoid harm or cause harm? 
It actually takes a very small amount of vitamin C to prevent scurvy, and not much more to treat it. Don’t have exact amounts.
I was just curious which deficiencies are harmful when treated with a mega-dose of whatever the patient lacked. I had read, for instance, that calcium is what a patient with eclampsia needs, but a sudden big dose will kill (although that was James Herriot talking about dogs; no idea about a human)
Apparently the divide is generally between water-soluble vitamins and fat-soluble vitamins. As
BippityBoppityBoo noted, you’ll just piss out any excess water-soluble vitamins like Vitamin C (although too much all at once can cause nausea and diarrhea). But fat-soluble vitamins like A, D, or E can build up in your body and harm you.
Two exceptions are Vitamin K and the B vitamins. K is a fat-soluble vitamin but it appears to be harmless even in high levels. The B’s are water-soluble but B-3 (niacin) and B-6 (pyridoxine) can harm you if you take too much.
Thank you for humoring my tongue-in-cheek question. I was pretty sure you weren’t the nefarious sort.
IANAD, but in my nursing experience magnesium sulfate IV is most often the mineral-based drug used to treat eclampsia. A larger loading dose is given to control seizures and lower extremely dangerous hypertension, then a maintenance level of magnesium is continued. Very, very careful titration of the dosages are required because eclampsia is possibly fatal. It is so severe an emergency that a physician usually stands by to monitor and adjust the doses in real time.
And, yes, James Herriot is a great author. Brought me many a smile.
See Two Years before the Mast by Richard Dana, the true story of Dana’s own experiences in 1834-1836.
They have been without fresh produce for months, and one man is at the point of death from scurvy.
Beside the natural desire to get home, we had another reason for urging the ship on.
The scurvy had begun to show itself on board. One man had it so badly as to be disabled and off duty, and the English lad, Ben, was in a dreadful state, and was daily growing worse. His legs swelled and pained him so that he could not walk; his flesh lost its elasticity, so that if pressed in it would not return to its shape; and his gums swelled until he could not open his mouth. His breath, too, became very offensive; he lost all strength and spirit; could eat nothing; grew worse every day; and, in fact, unless something was done for him, would be a dead man in a week, at the rate at which he was sinking.
But they meet a ship with a cargo of potatoes and onions, and get a good supply of them.
The chief use, however, of the fresh provisions, was for the men with the scurvy. One of them was able to eat, and he soon brought himself to, by gnawing upon raw potatoes and onions; but the other, by this time, was hardly able to open his mouth, and the cook took the potatoes raw, pounded them in a mortar, and gave him the juice to drink. This he swallowed, by the teaspoonful at a time, and rinsed it about his gums and throat.
The strong earthy taste and smell of this extract of the raw potato at first produced a shuddering through his whole frame, and, after drinking it, an acute pain, which ran through all parts of his body; but knowing by this that it was taking strong hold, he persevered, drinking a spoonful every hour or so, and holding it a long time in his mouth, until, by the effect of this drink, and of his own restored hope (for he had nearly given up in despair), he became so well as to be able to move about, and open his mouth enough to eat the raw potatoes and onions pounded into a soft pulp.
This course soon restored his appetite and strength, and in ten days after we spoke the Solon, so rapid was his recovery that, from lying helpless and almost hopeless in his berth, he was at the mast-head, furling a royal.
[quote=“Velocity, post:4, topic:917470, full:true”]
I was just curious which deficiencies are harmful when treated with a mega-dose of whatever the patient lacked. I had read, for instance, that calcium is what a patient with eclampsia needs, but a sudden big dose will kill (although that was James Herriot talking about dogs; no idea about a human)
[/quote]But Herriot was probably talking about injecting directly into the bloodstream, which is much trickier than giving as food. For instance, an air bubble injection can be quite deadly, but an air bubble down the throat is either nothing or a burp.
Chugging a whole jug of orange juice isn’t exactly a mega-dose. The folks who advocate mega-dosing with Vitamin C generally go for more like a thousand times the RDA, and even then, it doesn’t cause much problems.
Short term, I’d expect the primary effect would be needing to pee a lot, just because of drinking that much water.
We’re not talking about normal people in good health, but someone with severe scurvy.
In the first-hand account I posted, only a teaspoonful of potato juice “produced a shuddering through his whole frame, and, after drinking it, an acute pain, which ran through all parts of his body”.
It doesn’t sound like it would have been a good idea to give him a larger dose.
Scurvy was an occasional problem aboard the British warships of Patrick O’Brian’s Napoleonic sea adventures. I don’t remember massive doses of vitamin C being given as a cure (although the ship’s surgeon certainly knew how to treat the malady, supplies permitting), but I do remember that a telltale sign of scurvy was old skin wounds reopening, or new ones not healing.
But it wasn’t the miniscule amount of vitamin C that caused his reaction but the amount of food/liquid. The OP is problematic in that regard.
That tiny amount of liquid? What makes you think that?
Some degree of shock.
We’re not talking about a starvation victim, but a case of scurvy.
Who hadn’t eaten in days, and whose system was on the verge of shutdown.
So it was a teaspoon or two of liquid and not the vitamin C that caused the reaction?
Maybe it was just the reaction to eating a slurry of raw potato?
I’ve never tried raw potato, but I envision that might make me gag.
Any more creative explanations?
As instantaneously as the reaction was described, yes.