I have used the Gold Coin Grass tincture very successfully for my liver flushes. I had no adverse reactions.
A friend of mine tried it and broke out in horrible eruptive Acne on her face, chest and back. The GCG (and Chinese Bitters) contain Bupleurum, which is a very powerful herb known to "bring out eruptive diseases" and "dredge out old emotions of sadness and anger stored in the organs and tissues of the body". [from Michael Tierra's Planetary Herbology"]This is a good thing if you are ready for it. A bit overwhelming if you are not prepared.
You may want to start with a smaller dose, perhaps only 1/8 or 1/4 tsp and work up the recommended amount to allow your system time to adjust.