Sexual response libido

From a simple psychopharmacological perspective, the human sexual response can be divided into three phases, each with distinct and relatively nonoverlapping neurotransmitter functions, namely, libido, arousal, and orgasm. 

In summary, there are three major psychopharmacological stages of the human sexual response (Fig. 14—7). Multiple neurotransmitters mediate these stages, but only some of them are understood. Libido (stage 1) has dopaminergic dimensions to its pharmacology. The mechanism of arousal (stage 2), which is characterized by... 

In this chapter, issues in psychopharmacology related to sex and sexuality were discussed. This included an overview of the neurotransmitter mechanisms involved in the three psychopharmacological stages of the human sexual response, namely libido, arousal, and orgasm. Neurotransmitters that mediate each of these three stages were discussed, as well as drugs that facilitate and inhibit these stages. A specific introduction to the nitric oxide neurotransmitter system was outlined. 

To explore the psychopharmacology of the human sexual response, including libido, arousal and orgasm. 

A reasonable conclusion, about the acute effects of alcohol on male sexual response is that, similar to aggression, the disinhibition theory falls far short of explaining the information that is available. Rather, social and psychological factors seem to be important determinants of sexual response in men at low BACs and often work to increase libido. However, the pharmacology of alcohol begins to dominate at BACs greater than 0.05%, which cause a decrease in arousal and sexual competence. 

The mechanisms by which thiazides affect erectile dysfunction or libido are unclear, but it has been suggested that they have a direct effect on vascular smooth muscle cells or reduce the response to catecholamines. Sexual dysfunction does not appear to be mediated by either a low serum potassium concentration or a low blood pressure. Since sexual dysfunction can adversely affect the quality of life of hypertensive patients, physicians or health-care providers should take an accurate baseline sexual history and monitor sexual status for changes during therapy. If there are significant changes in sexual function, diuretic therapy can be withdrawn and an alternative drug class substituted. However, not uncommonly sexual dysfunction will persist despite withdrawal of the diuretic, suggesting that elements of the hj pertensive state itself contribute to the process. 

There is indirect evidence that reproductive outcomes might be affected (decreased libido, impotence, and sexual dysfunction have been observed in manganese-exposed men). The available studies on the effect manganese has on fertility (as measured by birthrate) is inconclusive. Two studies in men occupationally exposed to manganese show adverse effects on reproductive parameters one measured sexual dysfunction, the other measured semen and sperm quality, but neither measured birthrate in wives of affected workers. Impaired sexual function in men may be one of the earliest clinical manifestations of manganism, but no dose-response information is currently available, so it is not possible to define a threshold for this effect. There is a lack of information regarding effects in women since most data are derived from studies of male workers. 

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