How can you know when ringworm is gone?

Rash resolves: There is no scaling or redness and the itching should be gone.

Ringworm: You can know for sure that ringworm is gone only when there is absolutely no more itching or flaking in any part of the body for at least two consecutive weeks. Dermatologists recommend continuing the use of topical anti-fungal medication even if the rings are not longer as prominent, because ringworm has a high percentage of re-occurrence.

Rash is gone: Apply a topical antifungal treatment that you can buy over the counter to the involved skin several times a day until 1 week after the rash has resolved. You can use the same treatments that are used for athlete's foot.