Yes, I've taken it for years with very good results.
Be sure it is Flush Niacin as it is the flushing that helps to raise HDL. Also, you really must ramp up the dosage very slowly. Try to find the lowest cap dosage, I think it is 150 mg., and you might even break that in two to start. It's all right to get some flushing but you don't want to become overwhelmed. Eventually you would want to be taking 1200 to 1500 mg. a day, with food.
There have been many discussions about this on the High Cholesterol board here. You might want to check it out. You might aslo want to post your lab numbers there. Cholesterol is made up of components. So you need to determine what exactly needs to be done based on those values: increase HDL? lower LDL? lower Triglycerides?