The paper mentions that finasteride passes through the blood-brain barrier and affects the conversion of progesterone to allopregnanolone, where low levels of allopregnanolone are associated with depression. Together with the correlational evidence for depression and suicidality, this presents a reasonable picture for concern.
Since there is a known central activity, it also raises the question -- in fact the article explicitly mentions it -- of whether a brain-sparing analogue of finasteride might not show the same side effects.
The apparent connection to "masculinity" or "feminization" may be a red herring. Excessive concern about "sex" effects in biological systems kind of reminds me of the alchemical theory of the four elements. It's not a great way to analyze the complicated effects of medicines.
Since there is a known central activity, it also raises the question -- in fact the article explicitly mentions it -- of whether a brain-sparing analogue of finasteride might not show the same side effects.
The apparent connection to "masculinity" or "feminization" may be a red herring. Excessive concern about "sex" effects in biological systems kind of reminds me of the alchemical theory of the four elements. It's not a great way to analyze the complicated effects of medicines.