Hi, I Have Dark Marks On My Skin And I've

Hi, I have dark marks on my skin and I've tried everything but they're still on. I saw an advert about Demelan cream being able to remove them, will it really help? I'm not quite sure about the product and I've also used some products in the past that only increased my dark marks so what if Demelan also repeats the same problem and add more dark marks to my face?

I also have another problem...my skin has suddenly developed some sensitivity to the sun that I really don't understand. I get these really dark rough skin (almost like lizard skin) all over my neck and face every time because it is really hot and it's impossible to not be exposed to the sun or the heat. The skin comes and goes, I get it then it heals but it will then start all over again and it leaves my face and neck with really bad marks, even when using sun screen it doesn't help. I'm not necessarily exposed to direct sun most of the times because I never walk in the sun but the heat still affects me. I need something that will help my skin's sensitiveness to the heat and the sun because now it's getting worse I don't know what to do. Please assist me, anything to overcome this problem.