I have a rash on my legs and stomach...?

and back anywhere my shirt or pants touch my roommate change the washing powder and i know that has to be the reason i went and bought some other kind i always use and started washing my outfits in that how long will it take for my skin to stop itching it has got bad it started the past week i could not figure out what was wrong. Is there anything i can do to stop my body from itching and heal faster???|||It is going to take a while to stop itching. You can use benedryl to help reduce the itching while you wait.|||I had the same thing. Now listen to what I am saying and listen well. Go to a Doc. what happened was she gave me medication to take it way and it worked!! with in 2 days my rash looked better!!!|||Not long. Go buy some cortizone, that will keep it in check and stop the itch.