You have to correct the term used.
Its not a rapid ejaculation but a Premature Ejaculation Syndrome.
A man reaching the orgasm or climax very soon after the stimulation for sexual activity soon after or even before the penetration into the vagina and discharging the semen well before the orgasm of the female is called as PME or Pre Mature Ejaculation Syndrome.
Causes of PME:-
1.Likely to ejaculate prematurely if there's a long gap between sexual sessions.
2.Sex performed under FEAR,FORCE,COMPULSION,of any thing.
3.New persons at sex.
4.Old age.
5.Diseased state of the person
6.Anxiety Neurosis or any other neurosis
7.Arterial ill healths,The penis artery is clogged with fat and cholesterol with increasing age.
8.Diabetes.
9.Ischemic Heart Diseases.

Answered by Dr.Anil , an ibibo Advisor, at 4:53 PM on March 10, 2008