Drug:
RIBOFLAVIN
Riboflavin is vitamin B2

Side effects:
Deficiency of riboflavin is not common in the U.S. because this vitamin is plentiful in the food supply. Deficiency symptoms include dry and cracked skin and eyes that are sensitive to bright light.

There is no known toxicity to riboflavin. Because riboflavin is a water-soluble vitamin, excess amounts are excreted by the body in the urine.

 

Source:
http://www.umm.edu/ency/article/002411sid.htm