What Causes Measles Like Rashes On Hands?

HI I have a rash on my right arm and left arm. The rash on my right started on the fingers and have spread to the elbow. Initially there were small bumps with a small white heads. The itching was intense. The rash looks like measles. I have been using benadryl and calamine lotion or calamine lotion with tea tree oil. In the past i have applied sulfur shampoo and let it stay on for an hour. I have also done dead sea salt soaks and put the salt crystals on an area of the wrist that was very itchy. The itching seems to be getting better. I have had this for 3 months. The rash now looks like measles. It is not measles as I had measles as a child and later on had the vacinnation for measles as an adult.