I didn't answer the part of your question about whether or not spaying or neutering would help with discoloration of the grass by urine. (vetinfo.com)
Most people notice skin discoloration on their cheeks, forehead, chin and bridge of their nose. (sciencedaily.com)
I do have some areas of discoloration on my face, and this product has really really lightened up these areas, and I couldn't be more thrilled with the results. (beautylish.com)