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服用Finasteride的Reflex Hyperandrogenicity現象

[日期:2010-10-29] 來源:轉載及本站加以編輯  作者:佚名

在國外有一些服用Finasteride的網友,因為服用之後出現一些身理特徵(易出油、易長青春痘),或是懷疑效果,而會提到一個名詞『Reflex Hyperandrogenicity』。



到底什麼是reflex hyperandrogenicity呢?是雄性激素接受體對DHT更為敏感? 或是增加的睪固酮對毛囊產生負面的影響,反而影響效果? 此外,外用抗雄激素會出現這種效果嗎?

Reflex Hyperandrogenicity照字面上的翻譯是『反射性過多雄性特徵』,主要症狀是體毛增加,或是皮膚或臉部變得更會出油等。我找了Hairlosshelp.com與Dr. Peter H Proctor的說法,翻譯給大家參考。

當雄性激素在體內的作用變少,例如通過降低DHT的或全身性的激素受體阻斷劑,身體就會尋求一個平衡,這個過程被稱為上調(upregulation)。

這可能需要採取增加激素的生產和(或)增加組織對其他激素的敏感性的形式進行。之所以在臨床中,發現服用Finasteride的副作用會逐漸消失,就可能是由於上調的作用。

但有一小部分人,可能是這上調進程超過了標準,造成明顯的hyperandrogenicity 。這會在身體上出現一些特徵,包括臉部出油增加,粉刺、暗瘡(青春痘)增加,甚至提高性慾。

在某些情況下,hyperandrogenicity反而強過了Finasteride對雄性禿掉髮的改善作用,這是可能發生的,但也僅限極少數人。(Hairlosshelp.com)

Reflex hyperandrogenicity 是結合了睪固酮增加以及組織對男性荷爾蒙的敏感度增加的結果。後者部分原因可能是由於雄性激素接受體數量的增加。

Reflex hyperandrogenicity的強度是與抗雄激素的強度成正比。它同時也限制了使用抗雄性激素療法的使用,例如在治療攝護腺癌的同時,大多數這類病人的性功能也會失去或受到影響。

由於Finasteride的作用大多局限於組織上的第二型5-AR還原脢,降低其活性。所以會引發較少的Reflex hyperandrogenicity。所以,服用Finasteride來治療雄性禿掉髮還是有所成效的,也可降低治療過程中的副作用,如性慾減低等。至於目前在臨床階段的Dutasteride,可以抑制兩種類型的還原脢活性,但是否能夠確定其安全性與副作用,就等待其結果發表了。

外用的抗雄性激素產品,例如 spironolactone,並不會引起睪固酮的增加,也是有所幫助。

剛開始服用Finasteride的初期掉髮增加可能導致髮量還是在虧損的階段,這是由於頭髮生長刺激導致正常的頭髮掉落與替換,這並不是由於Reflex hyperandrogenicity所導致,畢竟很少發生。

(Peter H Proctor, PhD, MD)

以下摘錄Hairlosshelp.com的原文及另一網站的病人及醫生提及Reflex Hyperandrogenicity的對話:

What's reflex hyperandrogenicity?

A: When the effects of androgens in the body are lessened, e.g. through lowering DHT or by systemic hormone receptor blockade, the body seeks equilibrium through a process called upregulation. This can take the form of increased hormone production and/or increased tissue sensitivity to the remaining hormones. The reason side effects usually gradually disappear with finasteride is probably due to such upregulation. In a small percentage of individuals, it may be that this process overshoots the mark, resulting in significant hyperandrogenicity. This is marked by such signs as greatly increased facial oil, increased pimples, and greatly elevated libido. It's possible that in certain cases such hyperandrogenicity overcomes the hair-protective effect of, say, finasteride, though this does not appear to be the case for the vast majority of people.

(From Hairlosshelp.com)

Propecia and Reflex Hyperandrogenicity

Dr. Rassman, if you could, please answer this question. It’s very important, I’ve seen a ton of people online that really need this clarified for them by an expert in this field. Can Propecia cause Reflex Hyperandrogenicity, thus actually accelerating your MPB and, if so, what are the symptoms? I can’t tell if this is happening to me or not. Also, if I have lost hair due to Reflex Hyperandrogenicity is that hair gone forever or is there a chance I can get it back?

HairLossHelp.com has a good explanation of reflex hyperandrogenicity –

“When the effects of androgens in the body are lessened, e.g. through lowering DHT or by systemic hormone receptor blockade, the body seeks equilibrium through a process called upregulation. This can take the form of increased hormone production and/or increased tissue sensitivity to the remaining hormones. The reason side effects usually gradually disappear with finasteride is probably due to such upregulation. In a small percentage of individuals, it may be that this process overshoots the mark, resulting in significant hyperandrogenicity. This is marked by such signs as greatly increased facial oil, increased pimples, and greatly elevated libido. It’s possible that in certain cases such hyperandrogenicity overcomes the hair-protective effect of, say, finasteride, though this does not appear to be the case for the vast majority of people.”

The term “reflex hyperandrogenicity” is a new one to me, and while I unfortunately do not have the answers to your questions directly, hair loss from genetic causes in men is usually not reversible.



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