on vitamin C a few years back and, along with a spicy diet and high stress levels, burned the lining of my stomach/esophogus. I had to treat it like an
ulcer and patiently wait
for it to heal.
When you lay down at night, you are also more vulnerable to acid reflux because you don't have gravity to help keep things down.
While vitamin C is vital for health, and any unnecessary amounts are naturally flushed out of your system, you still run the risk of developing an overly acidic stomach.