Where did you acquire it? Generally, oral is the way to go if you don't experience sides and this is true of many meds like spironolactone, minoxidil, dutasteride, and progesterone among many others. Pills are easily with little to no time or effort necessary for ingestion/application.
Yes and it does work, I been on Topical Finasteride since 2010, see below the compound pharmacy MAA I use and you can compound the mixture with minoxidil and other anti androgen blockers.