I understand that a 1mg dose of Propecia is recommended. What I want to know, however, is how much more hair grew at a 2mg dose vis-a-vis the 1mg dose — 10% more? 15% more? I know these data exist. So, what incremental improvement might there be with a 2mg dose?
While it’s quite possible that the data for 2mg finasteride hair loss treatment benefits exists, I don’t have it, I don’t recall seeing it, and I’m not sure if it was ever made available to the public.
I do know that there were studies that looked at high dose and low dose finasteride (prior to Propecia becoming available) for treating hair loss. More is not better and I am not aware of a 2mg study showing any additional benefit. The stories that I do hear are anecdotal.
You’re right that once you discontinue Propecia (finasteride 1mg) treatment, your hair loss resumes. For me though, since I originally had crown loss, I tried finasteride to see if I could increase the hair in the crown. At that point, my crown was clearly stable and I did not gain anything from the finasteride.
“Improves Hair and Scalp Health” is a claim that the FDA would call “puffery”. Puffery is allowed for cosmetic claims. You correctly pointed out that it is a loosely based statement lacking in specifics”. This is characteristic of puffery. It just as easily could have said “livens up your hair” even though we all know hair outside the body is not alive. 
I don’t recommend Viviscal, as it hasn’t been proven to my satisfaction to treat hair loss. It also isn’t FDA approved, as it is just regarded as an over the counter supplement. The key ingredient appears to be a marine protein extract, so if you’ve got a fish allergy you should steer clear. Another key ingredient is vitamin C. While the product might help nourish your hair, I don’t know that it would treat hair loss, particularly if it is genetic in nature. Otherwise if you wish to use it, that is your choice to make.
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