I ve started having these brownish colored spots appear on the tops of my feet and now my ankles and its starting to spread up towards my leg above the ankles. They started out as a few spots here and there on my feet and have spread to the point that my feet look like they are dirty despite scrubbing them religiously. I m in no pain and no discomfort other then the weird appearance that my feet look dirty all the time now. I m worried that it will keep spreading and will continue up my legs and be very noticeable once on my legs. I m wondering if its a circulation problem or something more serious? Any help would be greatly appreciated. I m a 35 year old female, smoker, take fentanyl patches and Demerol for pain on daily basis. Not sure if this is a reaction to my medications or what to think?