. >> so there's currently one medication that is approved for preparing it's a co- formulateed drug it is a high toshl ability there's a startup symptom a few week people usually have a gastro upset that goes away most people can handle that but it's important to have a physician for that and as far as the cost effectiveness to provide it free for everyone i don't have those numbers colleen do you have those numbers about providing it for free no, i'm sorry we don't have those numbers. >> dr. grant may have more to add. >> dr. grant. >> there the cost effectiveness depends on who uses prepare and people that need it the most use it the mothering most san francisco overall as a new snaps people taking home prep have a higher instance of hiv this can be cost effective prep is cost saving if the hiv