I have a patch of freckles that appeared on my feet about an inch above my toes and it slowly spread up my leg and within the past six months or so it s spread halfway up my calf. I have psuedotumor cerebri and am on gabapentin, verapamil, and amytripiline (sorry for the spelling). I also have bipolar disorder and take abilify, zoloft, and lamactil. I am overweight, 22, I m of English decent, and I have no other patches of freckles on me. They are a light brown color and have been getting darker as it spreads. The area it is in is hardly ever exposed to sunlight because I always wear pants and never flip flops or sandals. When I press down on my skin the freckles do not change color. What could cause a rash like this?