Hormone blockers for transgender people

Hormone blockers or hormone inhibitors are drugs that reduce or stop the effects of hormones in the body. Most work by stopping them from being absorbed, but some drugs slow or stop their production.

These drugs have been safely used for decades to control sexual maturation in youth who are not gender incongruent. They are used for the same purpose in gender incongruent youth. This allows youth to avoid an unwanted puberty and to delay decisions on further medical steps.

Adults take hormone blockers for a number of reasons, including as part of cancer treatment, for contraception, or as part of a gender transition.

Androgen reduction and blocking

Androgen blockers have several names:

  • antiandrogens
  • androgen antagonists
  • testosterone blockers

Human bodies produce a number of androgens. These cause masculinizing effects. The two key androgens are testosterone and DHT.

  • androstenedione (A4)
  • androstenediol (A5)
  • androsterone 
  • dehydroepiandrosterone (DHEA)
  • dihydrotestosterone (DHT)
  • testosterone

Some people want to reduce androgens in their bodies for any number of reasons:

  • reduce or prevent certain health issues
    • precocious puberty
    • some cancers
    • some tumors
    • adrenal gland function
    • diabetes
    • high cholesterol
    • high blood pressure
    • heart disease
  • reduce or prevent masculine physical traits
    • scalp hair loss
    • facial hair growth
    • body hair growth
    • oily skin
    • dandruff
    • changes to hair and nails
    • acne
    • height
    • vocal deepening
    • skeletal development
      • skull
      • hands
      • feet
      • nose
      • shoulders
    • pubertal development
    • muscle mass increase
    • body fat decrease
  • change body odor
  • reduce or prevent increase in sex drive
    • unwanted spontaneous arousal
    • unwanted sexual thoughts
    • unwanted sexual behaviors

Estrogen reduction and blocking

Estrogen blockers have several technical names:

  • antiestrogens
  • estrogen antagonists

Some people want to reduce estrogens in their bodies for any number of reasons:

  • delay or prevent precocious puberty
  • reduce or prevent feminine physical traits
  • fat redistribution to lower body
  • fat redistribution in face
  • body fat percentage
  • hip widening
  • breast growth
  • brittle nails
  • skin thinning and drying
  • hair drying and breakage

Progesterone reduction and blocking

Progesterone blockers have several technical names:

  • antiprogestogen
  • antiprogestins
  • progesterone antagonists

Some people want to reduce progesterone in their bodies for any number of reasons:

  • emergency contraceptives
  • abortion
  • treatment of uterine fibroids
  • treatment of some breast cancers