|WikiProject Pharmacology||(Rated C-class, High-importance)|
re that last edit: An Antiandrogen blocks the effects of androgens on the androgen receptors.
Androgens are a class of hormones that act as the male sex hormones by binding to the androgen receptors of the body and effecting their biological effects.
An Antiandrogen by blocking the action of androgens (such as Testosterone and Dihydrotestosterone) will cause a severe form of male menopause, or andropause with significant negative effects on the sexual and reproductive systems of a male, such as a loss/reduction of the ability to get and maintain an erection, decline in sperm production and infertility, as well as reversing the positive effects that testosterone/androgens have on all the other cell and tissues of the body, which includes muscles, bone, brain, nerves, skin, hair, heart, kidneys, bone marrow etc.
To understand the physiologic effects of an Antiandrogen on the body one must first understand the biological effects of Testosterone and androgens on the androgen receptors in the body.
Androgens are any molecular structure that will bind to and activate the androgen receptors. This usually means testosterone and dihydrotestoterone, and their active metabolites, but includes many synthetic steroids.
The androgens are only one of five different kinds of natural steroid hormones, (steroid refers to sterol ring, which is cholesterol, and the five different classes of steroid hormones in mammals are all synthesized from cholesterol. In addition to the androgenic steroids (made mainly in the tesicles and to a lesser degree by the adrenal glands), includes estrogens and the progersterones (made mainly in the ovary and the corticosteroids and mineral corticosteroids (made in the adrenal glands).
Androgen receptors are present in very high concentrations in the tissues that form the external genitalia (penis and associated structures) such as the pelvic muscles and prostate, scrotum and testicles. The rise in testosterone and androgen levels at puberty causes the developement of the secondary sexual characteristics that are part of the changes in a boys body at puberty.
Before birth and during fetal development blocking the androgen receptor of a developing male fetus with an Antiandrogen would prevent the development of the a penis causing the male infant to be born with female external genitalia (that is a vagina without a cervix or uterus, and clitoris. As well the testicles would remain undescended. During fetal development any male fetus who cannot respond at the cellular level to Testosterone, whether it is from taking an anti-androgen like Bicalutamide, or 5-alpha-reductase inhibitors, or is a male who has inherited a defective gene causing a defective androgen receptor or defective 5-alpha reductase enzyme and cannot produce dihydrotestosterone will will not develope a penis. Such males are usually phenotypically identified as a female at birth.
In adult males blocking the androgen receptors by Bicalutamide or other Antiandrogen, and eliminating the effect of Testosterone and the other androgens from binding and stimulating the cellular effects of androgens, Bicalutamide will cause a decline in sperm count, infertility, and a sexual difficulties.
The effects of blocking the androgen receptors and blocking the effects of androgens in the body will have significant effects on the ability of a man to get to get and maintain an erection, resulting usually in profound impotence, and a dramatic reduction in the response to erectile dysfunction medications.
Blocking androgens receptors in the brain will eliminate the inhibition of Testosterone on the release of Luteinizing hormone (LH). Since the body will not detect any Testosterone/androgens and their will be a dramatic rise in Luteinizing hormone secretion resulting in a very significant rise in Testosterone and Estrogen levels.
Since an Ant androgen like Bicalutamide will block the effect of Testosterone on all tissues, there will be no response by the body to the increased androgen levels, but the rising sex hormone production will increase the Estrogen levels in the man to be much higher than they would be in a man who has not been taking Bicalutamide. The Estrogen levels will rise until they are high enough to suppress the release of LH which is causing the Estrogen and Testosterone levels to rise. This rise in Estrogen level stimulated by the blockade of the androgen receptor is why some of the side effects of Bicalutamide is breast tenderness and gynecomastia. As well other feminization effects will occur such as fat accumulation on the hips and thighs.
If Bicalutamide is combined with an LHRH analogue or surgical castration then the elevation of Estrogen levels will be prevented and the risks of excessive estrogen will be reduced. But blocking the rise in Estrogen levels will dramatically increase the bone loss and osteoporosis that will result from the effects of Bicalutamide blocking the actions of androgens in the bone. Since both Testosterone and Estrogens are essential for normal bone metabolism, reducing the positive stimulation of both androgens and estrogens on bone metabolism will definitely increase bone loss and osteoporisis.
Muscle, tendons, joints, bone, and connective tissues will also be affected resulting in a loss of physical strength, reduction in bone density, osteoporosis,etc. The effects of an Antiandrogen blockade of the bodies response to Testosterone will be the the opposite of what happen to a boys body at puberty when Testosterone levels rise and Testosterone start to exert there effect on muscle mass and sexual function. And the effects of taking Bicalutamide will essentially be equivalent to a severe form of male andropause since there will be no effect of Testosterone or any other androgen in the body.
 External links
- Estrogens are not antiandrogenic. They are antigonadotropic, but that's not the same.
- Reduced functioning of male sex organs does not have to be caused by antigonadotropic effects (eg. from cyproterone acetate). Antiandrogens without such effects (eg. finasteride) can still cause disfunction.
- Progestagen explains the progestational/progestagenic (same meaning, different word) of cyproterone acetate better than progesterone.
-- Kimiko 21:09 5 Jun 2003 (UTC)
What exactly is the point of insisting that hirsutism is "male pattern" something? I found quite a few definitions that do perfectly well without "male pattern" and only speak of excessive hair. That is probably because there is no particular "male pattern" hair anyway - women have much much shorter and thinner hair, but it does not follow a different "pattern". Women don't even have less hair than men, on the average. The only "male pattern" thing with regard to hair is the opposite phenomenon - male pattern baldness. Since the reasons for hair loss in males are distinctively different from those in women, there is indeed a particular male pattern there. So kindly stop reverting this, it is annoying and false. -- AlexR 00:14, 1 Jul 2004 (UTC)
- Compare these definitions:
- <clinical sign, dermatology> Abnormal hairiness, especially an adult male pattern of hair distribution in women.
- Excessive growth of the hair. Also called polytrichia and polytrichosis.
- both from http://cancerweb.ncl.ac.uk/omd/
- These are common medical definitions of the terms. "Male pattern" is important because excessive androgen exposure doesn't stimulate all hair growth equally, but specifically some areas.
- Male pattern is false though, because as I said, there is no particular "male pattern" in hair growth. How about going by:
- The clinical distinction between hirsutism and hypertrichosis is that hirsutism involves hair growth in a secondary sexual characteristic pattern. For example, women with pigmented terminal hair growth in the beard, mustache, chest, and escutcheon areas have hirsutism and not hypertrichosis.
- and simply using "in a secondary sexual characteristic pattern"? Not that it helps this article, but if it makes you happy ...
- Male pattern is false though, because as I said, there is no particular "male pattern" in hair growth. How about going by:
- But if you insist, that's okay with me. It's your article after all :o) -- Kimiko 07:32, 1 Jul 2004 (UTC)
- Uh, yes, what an argument! Of course it is not "my article", I merely would like this article (like all articles) to be correct, nothing else. Besides, this is not even the article about hirsutism, in this particular article there is just a super-short explanation given what several medical terms mean. Everybody who wants more information about hirsutism will have to follow the link anyway. Therefore, starting some hot debates about the two words in brackets is quite strange, anyway. -- AlexR 10:30, 1 Jul 2004 (UTC)
Consequences on reproduction
Does the use of antiandrogenes make a man sterile? Or does it only reduce his fertrility drastically?
2007-03-15 Lena Synnerholm, Märsta, Sweden.
- as I understand it, it depends on the drug in question. Long-term use of androgen blockers will certainly cause atrophy of the gonads which may or may not be reversible. I believe that after a number of years, fertility may be permanently impaired. (Just my opinion. Not medical advice, etc) - Alison☺ 18:15, 15 March 2007 (UTC)
Don't worry! If I really needed medical advice I would directly ask a professional. Encylopedias may be good for curious people like me but they shuold be used on your own risk.
2009-06-30 Lena Synnerholm, Märsta, Sweden.
Male to female transsexuals
plz tell me what i use to male to female transsexual and which madisian i use n how much .and i can get easealy in indiaplz tell me the proper name of antiandragonic harmones that which name i can find it
This is not a proper place to ask such questions. Please ask a professional Gynaecologist instead!
Antiandrogen Withdrawal Response Removal
BI513 Editing Comments
I'm a biology student at Boston College and as an assignment for my class, Environmental Disruptors of Development I did research on antiandrogens and have updated the Wikipage. Advice and suggestions would be greatly appreciated! I will continue working on the page throughout this semester. Kbell90 (talk) 18:16, 2 November 2011 (UTC)Kbell90
Hi Kbell90, Great article! I love how well organized it is and clear-cut and concise. It flows, its informative, and its not so complicated that you can’t understand. I’d say so far so good. As for ways to improve on it, I came across a few different points you could consider adding.
The main question that kept popping up for me as I read was how do antiandrogens suppress androgen synthesis? In the Intro is the first time this mechanism is mentioned and again in the Mechanism section itself, however, it seems a little vague and I was left wondering well…if this is a separate mechanism than blocking the receptor, then how exactly are they suppressing synthesis. It makes sense that blocking the receptor would block androgen effects, but wouldn’t androgen levels accumulate if they aren’t binding their receptors as usual? How do the chemicals diminish these levels? These articles may help:
Also, how do androgens suppress gonadrotrophin in the case of pharmaceuticals? Is this a similar mechanism?
I would be interested in seeing a section on how one can avoid being exposed to these chemicals and to reduce exposure to children during development. Have they found any way to reduce these chemicals in the environment yet?
Here’s a neat article on how effects are amplified when exposure is cumulative…might be good to include a little blurb on this.
Is there any current evidence on how release of these chemicals into the environment is affecting the biodiversity of species and species reproduction?
One more thing, you mention that antiandrogens are classified as either steroidal or nonsteriodal. I was thinking that if someone was reading your article that was not in the scientific community it may be helpful to write a little on what exactly this means. I even found myself having to think for a minute about it. So something brief, but to the point to clarify would be helpful.
Hey! Your article was very interesting to read and well-organized. Basically, all of my questions were addressed by Hortonb. I was also very interested to see if there has been any research on the affects of exposure in children. Are there ways to reduce or avoid exposure to anti-androgens, especially for children (again already addressed by Hortonb)? http://onlinelibrary.wiley.com.proxy.bc.edu/doi/10.1111/j.1365-2605.2010.01051.x/full
Are there any parts of the United States or the world that seem to have been severely impacted by anti-androgens? This is in response to Hortonb asking about the chemicals affecting biodiversity. Are there certain places that have seen a huge drop in biodiversity that may be linked to anti-androgens in the environment? http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1874188/
I found an article on anti-androgen treatments and you do not have anything on treatments, so I thought it would be a good addition to your article. http://apps.webofknowledge.com.proxy.bc.edu/full_record.do?product=WOS&search_mode=GeneralSearch&qid=6&SID=2CIf6PkgomdkMGeggLi&page=1&doc=2 http://www.ncbi.nlm.nih.gov.proxy.bc.edu/pubmed/20096826
Hey! I thought your article was great. It has a lot of information but is easy to understand and it is well-organized. The other two also addressed some of my questions but here are some more comments and suggestions:
- I really think you achieved neutral point of view. The article has the good and not so good things about anti androgens. I thought this was great!
- Nice section on vinclozolin!
- You should link your paraben section to anthonna's butylparaben
- Maybe your could add a section on the overall regulations of those chemicals and pesticides that display antiandorgen effects. What is being done to decrease exposure level?
- You mentioned some difference between developmental exposure and adult exposure but maybe you could emphasize this more. Which is of more concern?
- I also think you could maybe add a section on how to reduce exposure to anti androgens. Here is a good article http://www.oeconline.org/our-work/healthier-lives/pollutioninpeople/solutions/pesticides
- I liked the section on phytochemicals and found it very interesting. But what are the effects? So anti androgens occur naturally in these plants, what impact does this have on the plant and the environment?