I started to get itching in my hair when I had ringworm on my side and groin itch already. I had some strong oregano oil in my cupbord so I used an eye droper and put quite a bit on. Use the good stuff not the cheap. It did not burn very much for me but avoid the genitals, eyes or mucous membranes. It will peel the skin off you and burn like hell. Put the oil on hair areas a couple times a day for about 5 days. It smells strong.
Also, the stain Gentian Violet is a strong anti-fungal but avoid the same tender areas. Gentian Violet stains everything dark purple so be very careful. Use a Q-Tip. Use it the same as Oregano Oil, a couple times a day for 5 days. Sometimes it works in 3 days but not always. Use latex gloves to avoid staining your hands. Gentian Violet is safe enough for babies. Put alcohol in a plant sprayer bottle and keep it handy for clean up with paper towels.