I was able to get rid of the ringworm rash on my daughter's back with neem soap and oil of oregano. I washed the rash with the neem soap really good twice and then let the soap sit on the rash for a couple of minutes on the second wash. After the soap was rinsed off and I dried the skin, I applied oregano oil and put a bandage on the rash. This cleared it up rather quickly. I washed the rash and put the oregano oil on twice a day, in the morning before school and after her bath at night. You can try neem oil too. My daughter couldn't tolerate the smell, it does smell pretty awful. Maybe it will smell less awful if it's mixed with oregano oil. She just had a small rash so attacking it topically got rid of it.
As for Clarkia or humaworm, I'd throw both at it! When I went on the humaworm, it was constipating and I ended up taking the Paragone that I had on hand with it and it got me going again.