I have had a red scrotum for 7 months, it has spread up my penis and my anus has a bad itch as well. penis is only red on the bottom and around tip?

Yeast infection: Likely fungal / yeast infection, try over the counter anti fungal powder, if persist see a dermatologist. Hope this helps.

Jock itch: Tinea cruris which is a fungal infection of the groin, buttocks and genital area a. .Jock itch causes an itchy, red, often ring-shaped rash in these warm, moist areas of your body. Jock itch gets its name because it is common in people who sweat a lot, as do athletes. It usually respond to topical anti fungals creams.