Jock itch is a common fungal infection that creates red, itchy rashes around people’s genitals, buttocks, and inner thighs. Though uncomfortable, jock itch is rarely a serious problem and can be cured using simple home remedies.. Jock itch is the common name for tinea cruris, a fungal infection of the skin of the inner thighs, buttocks and genitals, according to MayoClinic.com. This infection is most likely to occur in people who have moisture on the thighs, such as that caused by sweating.. Jock itch, medically known as tinea cruris, is a fungal infection caused by the fungus trichophyton rubrum. Jock itch affects both men and women and commonly occurs on the groin, buttocks, genital area and inner thighs.. "HI Dr Andrew I have had a jock itch type of irritation between the buttocks for many months now. Have used Clotrimazole Anti-Fungal Cream (Canesten) plus other steroidal creams to try and stop the itch.. Tinea cruris, most commonly known as jock itch, is a fungal infection of the skin. It belongs to a group of fungal skin infections called tinea.. Betamethasone and clotrimazole topical (for the skin) is used to treat fungal skin infections such as athlete's foot, jock itch, and ringworm. Betamethasone and clotrimazole topical may also be used for purposes not listed in this medication guide..