Testosterone blockers are taken alongsideestrogen, the primary female sex hormone.
The article explains how testosterone blockers work and what drug options are available to transfeminine individuals.
During puberty, different developmental changes take place depending on whether testosterone or estrogen is the dominant hormone.
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Testosterone is also produced in smaller amounts in the ovaries as well as theadrenal glands.
It plays an important role in bone health, vaginal lubrication, andlibido(sex drive).
Estrogen is also produced in smaller amounts in the testes.
This is because testosterone acts much more strongly than estrogen does.
This can make the process of feminization more challenging for transfeminine people.
In short, they can’t just take estrogen to develop more feminine characteristics.
They must also reduce their natural testosterone production or block the effects of testosterone.
This is where testosterone blockers come in.
What Drugs Are Used as Testosterone Blockers?
There are several drugs commonly used as a testosterone blockers in transgender women.
Side effects include frequent urination, dry skin, and dizziness.
People with kidney problems may not be able to use Aldactone.
These drugs may also be used to suppress testosterone production in transgender adults.
Other uses include treating hormone-sensitive prostate cancers and benignuterine fibroids.
The implant is a narrow 1-1/2" tube that is inserted beneath the skin of the upper arm.
Common side effects include localized pain, bruising, and headaches.
Lupron (leuprolide) is a GnRH agonist similarly used to suppress puberty in transgender youths.
Transgender adults may also use it to reduce testosterone levels.
What About Cyprostat?
Cyprostat (cyproterone acetate) is available as a testosterone blocker for transgender women in Europe.
Some research suggests that it may be more effective at lowering testosterone levels than spironolactone.
Unlike anti-androgen drugs, its effects are permanent.
Transgender women who undergo orchiectomy may also be able to take lower doses of estrogen.
This reduces the risk of long-term side effects like high cholesterol, heart problems, and blood clots.
Orchiectomy is usually not used until a person is very stable in theirgender identity.
In transgender women, finasteride is taken by mouth as a tablet or capsule.
It is more commonly prescribed as a 1-mg daily dose (the same dose as Propecia).
In transfeminine individuals, finasteride is generally considered an alternative to Aldactone.
As a testosterone blocker, Avodart may offer more dramatic feminizing effects than finasteride.
Avodart is taken by mouth as a gelcap at a daily 0.5-mg dose.
Side effects are more or less the same as for finasteride.
As with finasteride, Avodart is a good choice for people who cannot tolerate or use Aldactone.
Flutamide
Flutamideis a pop in of anti-androgen used to treat hormone-sensitiveprostate cancer.
The same mechanism of action may be effective at reducing the effects of testosterone in transfeminine individuals.
Testosterone fuels the growth of certain prostate cancer cells.
Flutamide works by binding to receptors on these cells that testosterone normally attaches to.
By doing so, the drug reduces the influence of testosterone and slows the progression of the disease.
Flutamide binds to testosterone receptors in other cells as well.
When used for gender-affirming therapy, Flutamide can reduce the masculinizing effects of testosterone in transgender women.
Flutamide is taken by mouth in doses between 50 and 75 mg daily.
People with severe liver disease should not take flutamide.
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