Premarin is a medicine commonly used to treat menopausal symptoms. It is an oestrogen and is created from the urine of pregnant horses. The name" Premarin" is derived from the first three letters of "pregnant" "mare" and the 'n' from urine. Aside from being used in females, Premarin shows promise for treating prostate cancer and is one of the most common hormones used to treat male to female transsexuals.

Male to Female transsexuals (MTFs) commonly use Premarin to bring about the changes needed to appear and feel more female. Premarin increases oestrogen and feminises the body. The effects of Premarin on the male body is well documented through the use of the medicine in MTFs.

Oestrogen and testosterone are what make a male or female appear masculine or feminine. One of the first effects of taking Premarin is an increase in oestrogen levels. This effect is the precursor to all other results from a male taking Premarin. Premarin is oestrogen, so once it is in the blood stream it circulates and effects other organs and bodily functions.

Because oestrogen is a female hormone its function is to assimilate the body to a female appearance and function. One of the most obvious effects of taking Premarin is its impact on sex drive. Males who use Premarin will experience a decrease in sex drive, loss or decrease of erectile functions, and often testicular atrophy (testicles shrinking) will occur.

Another common effect of using Premarin is loss of muscle and shifting of body fat. Women are predisposed to carry more fat in the hip, buttock and chest. When a male uses Premarin body fat will start to shift and redistribute. Fat will be less thick around the middle and shift to the areas where women often carry fat. Breast tissue will also develop as a result of increased oestrogen.

Whether using Premarin to treat a medical condition or to gain feminising effects, it is vital to speak with a doctor. Specifically, an endocrinologist (a doctor who specialises in hormones) will often have more experience with Premarin than a family practitioner. Only a doctor can prescribe Premarin. Hormones are powerful and Premarin comes with the risk of increased blood clots and liver problems. A doctor can carefully screen the body for pre-existing conditions.

Premarin is used to treat prostate cancer. Both testosterone and oestrogen have a strong effect on the prostate. In fact, men with high levels of testosterone are more likely to develop prostate cancer than men with healthy to average levels of testosterone. Premarin works by decreasing testosterone and shrinking the prostate.