I have experienced a massive drop in my libido lately that makes me a bit worried. I happened to have used niacin in the last few months a couple of times. Even though I doubt that niacin is the troublemaker, I am still curious to know your input. Could niacin affect ones libido in a negative manner? If not, what could be it? I am around 30 years old and I have never really experienced such a significant drop before. It has been like this for 3 months now.