Hi,
There are many possibilities, including psycological and physical reasons. Some medications can cause the problem too.
There are some tests to diagnose the problem. Treatments are depending on the cause.
For detail information, please see the following web site.
http://www.minddisorders.com/Kau-Nu/Male-orgasmic-disorder.html
Best Regards,
I do not know if you want to try herbs. There is one herb listed on PDR (physician's desk reference). It is indicated for erectile dysfunction. Its name is XXXXXX XXXXXX.
Medical Researcher
Hospitals