There are no permanent effects that I know of. You have to watch it. The tan creeps on you. One day you're slightly tan the next you look like George Hamilton.
Crazy how different everyone reacts... I was worried mine could be fake but after trying 3 suppliers I realize it just doesn't give me the usual nausea or erections. I start at 500-600mcg with no problem but I do get red skin flushing that is pretty bad in some places like my shoulders.