My 6yr son has a red line - rash-like running from the base of the penis by the scrotum to the tip of the penis (uncircumcised) - may i try fucidin h?

Need diagnosis: Fucidin h is an antifungal cream & contains hydrocortisone. We don't know if this is a fungal rash. Would advise taking son to his pediatrician or family dr. To diagnose because description of a "red line" is insufficient to make a diagnosis. Or you could send a photo via email for us to evaluate.

Median raphe?: There is a normal red-brown line that runs from the perineum (between anus and scrotum) up the middle of the scrotum up the ventral (bottom) side of the penile skin. It is called the median (or perineal) raphe. It is not a rash and does not need to be treated. That may be what you are talking about. On the other hand, if it is a rash, you can use any kind of diaper rash cream/ointment on it.