[surferjoe2007]

For WY extract I haven't seen anything stronger than 6% diosgenin (a saponin) and the whole herb is around 1% give or take. So it would take a bit. Probably around 3 grams up to tens of grams, or the equivalent extract (on the lower end to start until you get used to it). For example if it's 4:1 you use 1/4th as much. That's internally. Externally I can't say but I've heard of it being done before so you could gradual increase similar amounts until you get something.