Hello dear patient. Welcome and thank you for your query. As I can see from your case, it seems like there is rash due to venous insufficiency and this is most frequent cause of itchiness and rash in legs. You should wear elastic stockings, keep legs elevated and avoid long standing and sitting. YOu can apply aloa vere cream or Detralex. In severe cases you should do tests which include Doppler ultrasound or venography. This will reveal possible venous disorders which can be treated with medications or surgery respectively. Please let me know if you have further questions before meeting your primary care Doctor.