Husband on 1mg finasteride, this year restarted for 6 months daily. Can he continue taking it every other day instead of daily?

Studies have not been done. Anecdotal reports would suggest that it is probably close but these studies have not been done. Finasteride is FDA approved for 1 mg daily. Any other uses are 'off label' and one should check with a physician for full review before proceeding down this path.

You can use this drug at half the dose by taking 1 mg every other day. It will be 80% as effective at half the dose.