Whitening shampoo will not remove tear stains, in fact you can cause serious irritation to the eyes. Nearly all whitening shampoos need to be diluted to some level (some as many as 50 parts water to 1 part shampoo!). If you don’t dilute whitening shampoo your dog’s coat will be dyed purple/blue, and you may cause skin irritation and dryness. Optical Brighteners enhance the visibility of whiteness, and reduces visibility of yellow stains or discoloration. [Read More]