Lipid Lowering Drugs – Niacin Niacin (nicotinic acid) has a different mechanism of action. Its major effects are to reduce the production of the apo B-containing lipoproteins and to inhibit the mobilisation of free fatty acids from adipose tissue (Fig. 6.35). Use of niacin leads to a reduction in VLDL and LDL levels and is also associated with an increase in HDL-cholesterol levels.