Nandrolone, popularly known as Deca, is a classified as a progestin. Deca derives many of its benefits from its progestenic nature: including, but not limited to, increase IM fat storage and increased fluid retention in the joints from glucocorticoid(GC) stimulation.

Deca is the most widely used form of prescription contraception in the first world. Deca is superior to testosterone as a form of birth control because its progestenic effects which result in rapid onset of azoospermia. Progestins are used similarly in women, progestins given to women in birth control pills and other drugs such as norgestrel and norethidrone are classified as 19-nor-testosterone or 19 nor- progesterone derivatives. Natural progesterone plays an important role in sexual arousal- affecting GABA to a considerable extent. The addition of progestins like deca which compete with progesterone and decrease its production may result in drastically reduced sexual arousal. Interestingly enough, the chemical castration of sex offenders, is acheived through the use of a 19-nortestosterone derivative.

This brings us to the second most common problem with the use of progestenic drugs like Deca, the breast tissue has both PR(progesterone receptors) and ER(estrogen receptors) and stimulation of either will result in new tissue formation and growth. This will vary considerably from individual to individuals based on the numbers and ratio of receptors in the tissue. Some individuals have more PR, which will make them more susceptable to gyno. Another suspected factor is that there are slightly physiologically different PR, as well as ER and AR, which may effect binding and expression of synthetic progestins either positively or negatively.

The use of Anti-estrogens and Aromatase-inhibitors will help by reducing stimulation of the ER in the breast tissue. However, those with high concentrations of PR or PR whose physiology allows for greater binding or expression of progestins will be faced with developing Gynomacastia.

In short

1. deca dick is real

2. DECA does cause gyno 3. DECA is progestin it must be fought with anti-progestins

4. Use of Nolvadex and arimidex will help, but only by reducing ER stimulation.