Use an over-the-counter antifungal cream, spray, or powder to get rid of athlete's foot or jock itch. If symptoms don't go away, prescription-strength medication may help. To prevent getting athlete's foot or jock itch again, tell your teen to wash and carefully dry his feet and groin area after showering. Change socks and underwear every day. Alternate wearing different pairs of shoes to allow the insides to fully dry out. Dust the insides of socks and shoes with medicated foot powder.