I took MT2 at 500mcg several times a week typically, but got up to 500mcg every day for a while. I got ridiculously dark, had the typical darkening of freckles, some new freckles, moderate indigestion, as well as hyperpigmentation of parts of my gums. Basically, some parts of my gums turned from pink to a purple-ish black color. I took a several month break, and my gums returned to normal. The freckles didn't change, however. I now take it less frequently, basically a couple of times a month before tanning. My genetics make getting/staying dark relatively easy, so two MT2 enhanced tanning sessions a month will keep me as dark as you see me in my profile pic indefinitely.