Vascular disease is common in individuals who smoke or have diabetes, peripheral vascular disease, or hypertension. Any time blood flow to the penis is impaired, ED can occur. Drugs are also a cause of erectile dysfunction. Individuals who take drugs that lower blood pressure, antipsychotics, antidepressants, sedatives, narcotics, antacids, or alcohol can have problems with sexual function and loss of libido.Hormone deficiency is a relatively rare cause of erectile dysfunction. In individuals with testicular failure, as in Klinefelter syndrome, or those who have had radiation therapy, chemotherapy, or childhood exposure to the mumps virus, the testes may fail to produce testosterone. Other hormonal causes of erectile failure include brain tumors, hyperthyroidism, hypothyroidism, or adrenal gland disorders. Orgasm disorders
Anorgasmia
Anorgasmia is classified as persistent delays or absence of orgasm following a normal sexual excitement phase in at least 75% of sexual encounters. : 368  The disorder can have physical, psychological, or pharmacological origins. SSRI antidepressants are a common pharmaceutical culprit, as they can delay orgasm or eliminate it entirely. A common physiological cause of anorgasmia is menopause; one in three women report problems obtaining an orgasm during sexual stimulation following menopause. Premature ejaculation
Premature ejaculation is when ejaculation occurs before the partner achieves orgasm, or a mutually satisfactory length of time has passed during intercourse. There is no correct length of time for intercourse to last, but generally, premature ejaculation is thought to occur when ejaculation occurs in under two minutes from the time of the insertion of the penis.
Research
In modern times, clinical study of sexual problems is usually dated back no earlier than 1970 when Masters and Johnsons Human Sexual Inadequacy was published. It was the result of over a decade of work at the Reproductive Biology Research Foundation in St. Louis, involving 790 cases. The work grew from Masters and Johnsons earlier Human Sexual Response (1966). Prior to Masters and Johnson, the clinical approach to sexual problems was largely derived from Sigmund Freud. It was held to be psychopathology and approached with a certain pessimism regarding the chance of help or improvement. Sexual problems were merely symptoms of a deeper malaise, and the diagnostic approach was from the psychopathological viewpoint. There was little distinction between difficulties in function and variations nor between perversion and problems. Despite work by psychotherapists such as Balint sexual difficulties were crudely split into frigidity or impotence, terms which acquired negative connotations in popular culture. Human Sexual Inadequacy moved thinking from psychopathology to learning; psychopathological problems would only be considered if a problem did not respond to educative treatment. Treatment was directed at couples, whereas before partners would be seen individually. Masters and Johnson believed that sex was a joint act, and that sexual communication was the key issue to sexual problems, not the specifics of an individual problem. They also proposed co-therapy, with a pair of therapists to match the clients, arguing that a lone male therapist could not fully comprehend female difficulties.