How soon do you discover new radiant skin while using Neutrogena Healthy Skin SPF-15 FPS ?

I have Hyper-pigmentation or dark Melasma on my face.Tried everything nothing worked but someone told me Neutrogena Healthy Skin SPF-15 would work and it should clear my Hyper-Pigmentation or Melasma. I am using it daily since 3 weeks but barely see any changes.How long does it take to discover actual changes in my skin? Please help...
How soon do you discover new radiant skin while using Neutrogena Healthy Skin SPF-15 FPS ?
about 4 weeks.
How soon do you discover new radiant skin while using Neutrogena Healthy Skin SPF-15 FPS ?
I have sensitive skin (don't know your type) and Dr. Jeffery Dover's Flawless Effects was recommended by a skin type book I read. It's sold at the drugstore...and it worked, results showed immediately! Other brands (even the expensive stuff) didn't seem to show results for me.