How does ezetimibe increase hdl-c?

It doesn't: I'm not familiar w/ezetimibe raising hdl, just lowering LDL by inhibiting cholesterol absorption. Check out www.Zetia.Com & http://www.Merck.Com/product/usa/pi_circulars/z/zetia/zetia_pi.Pdf for more info.

It Does Not-only LDL: Zeta, aka ezetimibe, is a selective cholesterol absorption inhibitor. By itself, it typically does little to either blood cholesterol or lipoproteins concentrations, because internal production of cholesterol, body wide, simply increases to compensate (similar to vegan diet). However, if added to a statin, it typically lowers cholesterol, ldl-c & most importantly ldl-p, measured in nmol/l.