Can i use 1 spoon of rice vinegar (ingredients: water, ethanol, rice)/day in my diet when i am on accutane?

What's really in it?: It's almost certain you signed an agreement, when you started on accutane, not to drink alcohol. Keeping a promise is a matter of principle. If the "rice vinegar" is a concoction that someone makes from real ethanol as a folk medicine, you're breaking a promise. However, most "rice vinegar" has the ethanol oxidized to acetic acid. That's harmless flavor, though there's probably no health benefit.