'Women's Viagra' to Seek FDA Approval, AgainAn FDA advisory committee is meeting on Thursday to discuss whether flibanserin — a drug sometimes nicknamed 'women's viagra' — should be approved to treat low libido in women. If approved, the drug would be marketed as treatment for hypoactive sexual desire disorder, which is said to cause a low sex drive in women. Some supporters argue the drug has a role in gender equality and that women do not have the same resources as men to deal with various degrees of sexual dysfunction. The drug, owned by Sprout Pharmaceuticals, has been rejected by the agency two times already. The argument being that its benefit is not notable enough to outweigh its side effects which can include dizziness and nausea. Other pharmaceutical companies including Pfizer and Procter & Gamble have made attempts at drugs to treat lack of libido among women. So far they have not been successful. The FDA's Thursday meeting on flibanserin is open to the public.
力比多（libido）即性力。这里的性不是指生殖意义上的性，它被称为："力比多"（libido)，泛指一切身体器官的快感，包括性倒错者和儿童的性生活。精神分析学认为，力比多是一种本能，是一种力量，是人的心理现象发生的驱动力。
有时，性渴望会被损害或者减少，同样可能表现出无力甚至完全不表现，诸如无性所发生的那样。影响力比多的因素可以是心理的，也可以是生理的。力比多的缺失与不育症以及阳痿的联系也并非绝对。
心理因素 力比多的降低可以发生于心理的原因，比如说隐私以及/或者亲昵的缺失，压力，精神涣散或是抑郁。又或者是来源于环境刺激，比如说长期暴露在高强度的噪音或是强烈的光线当中。其他原因还包括：Depression 抑郁stress or fatigue 压力或疲乏 childhood sexual abuse, assault, trauma, or neglect 儿童性虐待强奸精神创伤或忽视body image issues 身体形象问题 sexual performance anxiety 性焦虑
生理因素 影响力比多的生理因素包括：内分泌问题比如甲状腺功能减退;人体血液当中可利用睾丸素水平;某些药物的影响（比如波斯卡（又名非纳斯特胺）以及米诺地尔），不同生活方式的影响以及，根据研究显示，自己伴侣的吸引程度和健康程度。遗传性性欲的缺乏，就如在无性人群中所经常看到的那样，也可以被认为是由生理因素造成的。生活方式： 体重过轻，过度肥胖或者是营养不良，由于正常荷尔蒙水平的失调，也会导致力比多低下。药物：力比多的降低也经常是医原性的，可能由多种药物引起，比如荷尔蒙避孕法，选择性5-羟色胺再摄取抑制剂以及其他抗抑郁药，阿片样物质和β受体阻滞药(治高血压和心脏病的药物)。在某些病例中，如PSSD（Post-SSRI sexual dysfunction），医原性阳痿或是其他性功能障碍可能是永久性的。睾丸素是人体中控制力比多的一种荷尔蒙。最新的研究显示，荷尔蒙避孕法如避孕丸（依靠雌激素和孕酮的共同作用），通过提高性激素结合球蛋白水平，引起女性力比多的降低。性激素，包括睾丸素，与球蛋白的结合后，便不可利用了。研究显示，即使停止荷尔蒙避孕法，SHBG水平仍居高不下，并且当下没有可靠的数据能够预测这种上升现象何时会下降。有人怀疑是否避孕丸以及其他荷尔蒙避孕法（甲羟孕酮避孕针，诺普兰植入等）通过后生性机制已经永久地改变了基因表达。如果不加处理，睾丸素水平低下的妇女将体验到力比多的丧失，而这反过来将会引起其一生人际关系的紧张，以及骨骼和肌肉质量的丧失。（低睾丸素可能也是某些抑郁症和精力衰弱的原因）。相反，雄激素（如睾丸素）在两性中普遍都与力比多有确定的关联。月经周期：女性力比多与她们的月经周期也有关联。许多女性在排卵前的几天里能够体验到高涨的性欲。
Mechanism: The proposed mechanism of action refers to the Kinsey dual control model. Several sex steroids, neurotransmitters, and hormones have important excitatory or inhibitory effects on the sexual response. Among the neurotransmitters, the excitatory activity is driven by dopamine and norepinephrine, while the inhibitory activity is driven by serotonin. The balance between these systems is relevant for a healthy sexual response. By modulating these neurotransmitters in selective brain areas, flibanserin, a 5-HT1A receptor agonist and 5-HT2A receptor antagonist, is likely to restore the balance between these neurotransmitter systems. 5-HT1A receptor activation likely plays a significant role in the empathogenic effects of serotonin releasing agents (SRAs) like MDMA ("Ecstasy") as well.
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