there topical antiandrogens I can use instead of
taking something internally such as finasteride?
Yes. Some things have been used topically to either
bind up receptors (spironolactone or estrogens) or
reduce androgens or diminish hormonal impact (azelaic
acid, pyridoxal B6, zinc, free fatty acids). There
is much debate about the efficacy of these agents.
The problem is a lack of study data regarding their
use in male pattern hair loss, though there are studies
suggesting why these agents may help.