Erectile dysfunction, also called impotence, is defined as a man?s inability to get an erection or maintain it long enough to have sex with a partner. For some men, impotence means they are unable to ejaculate during sex. Erectile dysfunction or impotence happens to most men at one time or another, but studies indicate that erectile dysfunction is more common in older men, so it is often associated with the aging process in men. Occasional impotence is often not seen as a problem, but when impotence continues for awhile, it can bring on great emotional distress for both the man and his partner.

Essentials for TCM Diagnosis 
(1) The disease is characterized by inability to have an erection of penis during sexual intercourse in males before climacteric.

(2) It can be attributive to excessive sexual activities, prolonged illness, weak constitution, frequent masturbation in youngsters, accompanied by lassitude, weak loins and knees, aversion to cold, cold limbs, or difficulty in urination with dribbling urine. 

(3) Impotence due to hypoplasia of sex organ or the use of drugs should be excluded.

(4) Distinguish impotence from premature ejaculation. Premature ejaculation refers to early ejaculation of semen at the beginning of sexual intercourse and inability to carry on sexual intercourse because of flaccidity of the penis immediately after the ejaculation. However, impotence means the inability to achieve a satisfactory penile erection. They present marked differences. Nonetheless, if premature ejaculation persists, impotance may ensue.