I would like to tell you my experience. I was taking a couple of antidepressants and I started to experiment on my own by adding/subtracting from my doctors recommendation. That was because my doctor knew NOTHING about herbs and botanicals, and my feeling was that I could do the research. Unfortunately, I found out that you CAN NOT mix certain biochemical compounds with antidepressants. It causes a reaction that either weakens or amplifies the effect of the pharmaceutical. I was using St. John's Wort, and as another person here says, that's a no-no because there are so MANY interactions with S.J Wort.
However, when I changed doc's (you should consider it), my holistic MD told me that Rhodiola is OK to mix with the pharma's because there isn't the same problem. I started with Mind Body & Spirit (I would highly recommend that product) which he suggested. I was able to reduce my pharma dosage in three months. The Rhodiola had a huge effect on me -- my outlook became very positive and I'd wake up EXPECTING the day to go great, which was a very different attitude for me!! So, to the person who cautions about Rhodiola below, I'd say that this isn't the case. I can't answer for Gotu K. but I can say that at least with R. rosea, they haven't yet found a drug interaction. The only caution on the box I have here (Verde Botanica) is "Do not take if bipolar."
I don't know why that is. I did find when I tried some cheap Rhodiola from a store that I got a bad headache and no results, so I'd say you have to stick with the good brands. If it isn't $20 or more, you're probably just buying the same Chinese stuff that most companies buy and resell from $5 to $15.
Good luck to you! Please, DO consider changing to a holistic doctor. Someone who knows these herbs can really be a resource for you.