The intensity of sexual desire in healthy men and women differs from one person to the other. Hypoactive desire, which affects millions of people worldwide, is probably the most underestimated, neglected, undefined, difficult to evaluate and treat, and frustrating sexual disorder. Health care providers are faced with a plethora of clinical studies on various other sexual disturbances but with a dearth of evidence regarding the proper diagnosis and management of low sexual desire, no objective tools to assess or measure it, and plenty of misconceptions and ignorance about it. Diminished desire or low libido in men is commonly, and erroneously, misdiagnosed and treated as erectile disorder (ED)—with very poor results in most cases.
The Greek physician and so-called father of medicine, Hippocrates (460—375 b.c.), attributed ED to man’s professional preoccupations and the ugliness of the female. Eighteenth- and nineteenth-century religious moralists maintained that it was caused by excessive sexual activities such as masturbation, prostitution, and promiscuity. ED has been “treated” over the years by witchcraft, exorcism, and religious counseling. Fortunately, ignorance and superstition about sexual function and dysfunction were eventually superceded (at least to some extent) by scientific examination and discovery.
The penis has been dubbed “the barometer of a man’s health,” and rightly so, as any abnormality in its anatomy, physiology, or functioning may reflect an underlying disease or disorder. Furthermore, the penis is considered to be the symbol of virility, power, manhood, strength, and authority. This explains the obsession of many men with the size of their penises. In an Internet-based survey of 52,031 heterosexual men, 66% rated their penises as average, 22% as large, and 12% as small (Lever J et al. 2006). Unfortunately, despite the seeming obsession with this vital organ among the majority of men (and quite a few women), most people are ignorant of even the basics of penile function and dysfunction. Here are answers to several frequently asked questions—and perhaps to some you’ve been unable to ask.
Sex is an integral part of an intimate relationship and forms the basis for a couple’s shared love and respect, but many people cannot fully enjoy these pleasures. A sexually dysfunctional man, for example, may lack the desire or self-confidence to participate in sexual activity. He may not be able to focus his attention on arousal activities. He may ejaculate prematurely, or lose his erection before his sexual partner is sexually satisfied, or he may develop and maintain an erection for a long time but without being able to reach orgasm or ejaculate.
To recognize erectile dysfunction (ED) and understand its causes, it is important to remember that penile erection is a continuous neurovascular phenomenon under psychological control and requires a proper hormonal milieu for its successful achievement. Recall these physiological mechanisms of erection, described previously: under sexual stimulation, impulses from the parasympathetic and nonadrenergic/noncholinergic (NANC) nerves cause the release of nitric oxide (NO, also possibly secreted from the penile vessels’ endothelial cells). NO enters the smooth muscle cells inside the vessels in the corpora cavernosa, where it stimulates the enzyme guanylate cyclase to produce cyclic guanosine monophosphate. This activates the enzyme protein kinase G to phosphorylate (add a phosphate group) to certain proteins that are responsible for regulating the tone of the smooth muscles in the corporeal arteries and sinuses, thereby contributing to the relaxation of those vessels and the consequent inrush of blood to the penis.
There exist fundamental rights for the individual, including the right to sexual health and a capacity to enjoy and control sexual and reproductive behavior in accordance with a social personal ethic. World Health Organization Guidelines
The pioneering work of Masters and Johnson in the 1970s shed significant new light on the possible causes of sexual dysfunction. Their publications emphasized the influence of religious orthodoxy, fear of failure, homosexuality, and maternal influence as contributors to erectile dysfunction (ED). Subsequent theories considered additional psychological factors such as the man’s “thinking” about sex, negative self-image and expectations, the partner’s needs and preferences, and the influence of marital conflict on sexual function. Recent studies have stressed the importance of not only anxiety, but also various physical conditions as major causal factors in ED. Although about two-thirds of the causes of ED are organic, psychogenic issues are still a critical part of male sexual dysfunction, and experts have not completely forgotten them. Psychosocial, lifestyle, demographic, marital, developmental, religious, and pharmacological factors may play a major contributory role in ED’s initiation or persistence, whether alone or, in a substantial number of cases, as a response to the sexual dysfunction. Emotional reactions to sexual dysfunction may be severe and should be addressed seriously in both the diagnosis and management of this devastating condition.
The phases of the male sexual response have distinctive physiologic characteristics (Lue T et al. 2004a) that include the erectile process, which is a continuing series of neurovascular events occurring within a normal hormonal milieu (primarily, an appropriate level of serum testosterone) and with an intact psychological setup.
Sildenafil citrate has been shown to be effective in a wide range of patients with erectile dysfunction and has been approved in the United States for this indication. The overall clinical safety of oral sildenafil, a potent inhibitor of phosphodiesterase type 5, in the treatment of erectile dysfunction was evaluated in more than 3700 patients (with a total of 1631 years of exposure worldwide).