Scalp ringworm is an antifungal disease of the scalp. It is the fungus that appears on the scalp and it can be treated by an effective medication only. Antifungal medicines are usually prescribed for such issues. Use of Griseofulvin is the initial choice for treating scalp ringworm. The course of this medication lasts from 8 to 12 weeks. You can either apply the liquid or crush the tablets in water to apply on the affected area.