When I was on the finasteride I experimented with the dosage a bit. I tried 0.5mg every other day, 0.25mg daily, 1mg every 3-4 days, etc... To be honest, I thought all those combinations were better than 1mg daily but my pecker was still feeling funny.
My side effects weren't so bad, the pecker was still functional but it didn't feel the same. If it was just one course of medication for a month or so, I would just put up with it and get on with my life for a month. However, intentionally stunning my libido everyday to keep a bit of hair was getting too much for me. I tried it twice for a month and I decided it wasn't for me.
There is a graph that shows how long the effects of a single dose of finastride lasts for.
Basically, a single dose of 0.25mg finasteride is effective for 3 days or so. You could try taking 0.25mg every other day, or once every 3 days.