Yes, that's it. So I can skip 200mg spironolactone if I just take 50mg cpa? Or is spironolactone safer even at this dose?
spironolactone is safer long term, CPA is way more powerful than spironolactone though, and you wouldn't even need 50mg cpa, 25mg CPA is almost equally effective as 50mg CPA.
Objective: The recommended dose of cyproterone acetate (CPA), an anti-androgen that is commonly used in the hormonal treatment of transgender women, is 50–100 mg daily. Our objective was to determine whether CPA at 25 mg daily would suppress total testosterone as effectively as 50 mg daily in transgender women.
Results: We divided the sixty-eight patients included in the study into 4 groups: group 1, CPA 25 mg (
N =31); group 2, CPA 50 mg or higher (N = 19); group 3, CPA dose lowered from 50 mg to 25 mg (
N = 15); group 4, CPA dose increased from 25 mg to 50 mg (
N = 3). The mean total testosterone on treatment was 0.9 nmol/L (95% CI 0.7 to 1.1) in group 1 and 1.2 nmol/L (95% CI 0.9–1.5) in group 2 and were not significantly different (
p = 0.087). In group 3, there was no significant difference between total testosterone levels before and after decreasing the dose of CPA from 50 mg to 25 mg,
p = 0.86. Group 4 was excluded from analysis.
Conclusions: We found that 25 mg of CPA daily was effective at suppressing testosterone levels to within normal female range when used in combination with recommended estrogen therapy in transgender women. Clinicians should consider using a lower dose of CPA in order to minimize potential adverse effects.
https://www.tandfonline.com/doi/abs/10.1080/15532739.2017.1290566