I mean, I think it should be fine because it's made from leaves and leaf tea is OK. Also, this is my 5th week on Lipotrim and I haven't broken ketosis as far as I can tell!
If I haven't used the facilities (ahem!) in like 3 or 4 days and it's making me headachey, I'll take one cup in the morning, usually gets things moving by that evening, or the next morning! If nothing by the middle of the next day I'll have a second cup. It's very gentle.
I tried Dulcolax once a few years ago too, I thought my stomach was going to explode from pressure!