Spironolactone (Spee-row, for short), is generally an effective and well tolerated T-blocker. Yes, it is principally a diuretic, but the reason drugs are commonly used for effects for which they are not indicated by the manufacturer is because it costs too many millions of dollars to get FDA approval for the other effects, and usually little profits available afterwards due to patent issues - not because they are either unsafe or un-effective. There are certainly also some cases with some drugs where this is not true, where there can be inherent dangers. Androcure (Cyproterone acetate - Cypro) is a powerful anti-androgen, but carries a risk (however small) of causing liver damage, although it is available in Europe (but not in the USA because there is no FDA approval for any use).
When one starts one of these T-blockers, the sudden drop in T can result in a shift of the Estrogen-Testosterone balance toward the Estrogen to T ration being higher. This can go on, apparently for some time, particularly because the male body gets at least some of its Estrogen by converting T to E. I'm not sure why, but apparently this conversion is eventually down-regulated, or there simply is not enough T to convert to sufficient E - eventually, development of female attributes (fat redistribution, breast growth, etc.) is curtailed.
Some, but not all, people experience mild breast development and fat redistribution, after beginning T-blockers. The reasons for the curtailing mentioned above is my speculation on why this development eventually stops. It would be nice to see a chart of serum bound T and E total amounts, ratios, and free hormones over time, beginning with just before a person begins T-blockers, in order to have a clearer picture of what is actually happening. If anyone has had those measurements performed on themselves, or if they know where such a chart can be found, please do let us all know.
