200mg a day but the safety of that dose hasn't been studied a typical dose is 20-40mg....it's also a med that isn't supposed to be used for more than 6-8 weeks...and I have no idea how it would interact with your other meds...thus for sure mention it to your doc before you even try it. I know my doc was even worried about herbal supplements etc so it's important to keep them involved with all your meds.