Before I created an account here, I think 2-3 years ago, I read many posts of an old user named "Bryan" (unfortunately he passed away and he will always be remembered). Even though I didn't know him well, I found his posts interesting and accurate. Recently I came across an old topic regarding the usage of oral spironolactone. He had a discussion with an another user about testosteron levels and oral spironolactone at 200 mg. According to Bryan, based on the oral spironolactone 200 mg study in Greece, which you can find in my OP as well, there were no marked changes in endocrine parameters".
Here's a reference: No marked changes in the endocrine parameters were observed as a result of treatment, with serum testosterone being slightly elevated in one of the female patients both of whom had polycystic ovary syndrome. A marked reduction in the rate of daily hair loss and an improvement in the trichogram score were noted during treatment, in all 4 cases, but with a partial relapse following its cessation (Table 1).
Even though there were only two males, I still find it rather fascinating.
So oral spironolactone 200 mg definitely lowers T levels, but not to female levels. That's why certain MtF people use, for example estrogen, estradiol, medroxyprogesterone, etc, along with oral spironolactone during their transition to really reach female levels.
The only thing I don't get is why 13 % of oral spironolactone users get gynaecomastia. Do they get it when they use it along with HRT, so the full package?