Hi,
Thanks for the question. There are a few possible reason for the rash on the groin. It could be due to fungal infection, eczema or intertrigo or even a combination of the above.
Gentrisone is made up of a combination of a potent topical steroids, an antifungal and antibacterial cream, so it may treat both an inflammatory condition like eczema and fungal infection.
If the rash is persistent and recurrent it may be useful to do a fungal scraping to confirm or rule out a fungal infection.
If it is indeed a fungal infection, I agree that treating with a pure antifungal cream, rather than a combination cream is far more effective in settling the fungal infection and you should continue for a further 2 weeks after the rash has cleared. In some cases, oral antifungal tablets may also be used.