I am 70 years old and diabetic for last 10 years, but under control. Few years back i developed some itching sensation on my foot and dark patches on skin appeared. This happen when I travel from Kerala to Bangalore,probably from warm climat to cold climat.My Doctor suggested to apply Oilatum cream on the dark patches and I used to get relief. Nowadays the dark patches is moving up from ankle level to thigh level and develop seviour itching sensation during winter season and I have to apply the cream almost every day. Can you explain what is the basic reason for this phenomina and a suggest a treatment.I am a resident fro Kerala often travel to Bangalore. Thanking you