Ringworm (Tinea Corporis): Course and Treatment

Ringworm is a superficial fungal infection (dermatophyte) that does not spontaneously appear and disappear over a day/night cycle. Lesions typically expand slowly over days to weeks, with central clearing and active, scaly, erythematous borders.

Typical Course

• Incubation: 4–14 days post-exposure.
• Progression: Slow centrifugal spread; may coalesce.
• Without treatment: Persists for weeks to months; can spread to other body sites or contacts.

Diagnosis & Treatment

• Clinical diagnosis confirmed by KOH prep (hyphae) or fungal culture.
• Topical antifungals (terbinafine, clotrimazole, ketoconazole) 1–2× daily for 2–4 weeks.
• Oral antifungals (terbinafine, itraconazole) for extensive, resistant, or hair-bearing areas.

If a rash appears and disappears daily, consider urticaria (hives), contact dermatitis, or other transient reactions—not ringworm.