massive amounts of Vit C you can acidify the urine. Urine is supposed to be
a little alkaline. By changing the pH of the urine, you can change the
excretion of drugs, so keep that in mind.

Your doctor should know this Vit C intake, because it can skew some blood tests, esp blood sugar.

There was a paper on our health news forum which went off line sadly.
But it showed increased stomach cancer when Vit C was taken in high amounts with food.
So it recommended using it only on an empty stomach. The Vit C reacts with nitrosamines to
create carcinogenic compounds. I wish I had copied the story...and have since not found it
again.