10-20 minutes, once it's bound by igfbp's about 20 hours.
Same as regular human igf-1.
it took me less than thirty seconds to find this answer on this forum. I'm not trying to be an ass and single you out(matter of fact I still went out of my way to answer your question), but 40% of the 85% of the worthless posts on this site are people asking questions that are easily discoverable with a little digging.