Hyperlipidemia is abnormally elevated levels of any or all lipids or lipoproteins in the blood. These are drugs which lower the level of lipids and lipoproteins in blood. They are transported as complexes of lipid and proteins known as lipoproteins. Lower protein/lipid ratios make for less dense lipoproteins. The lipid components of lipoproteins are insoluble in water. While circulating in blood, chylomicrons exchange components with high-density lipoproteins (HDL). Foam cells are fat-laden M2 macrophages containing low density lipoproteins (LDL). Some modifications can produce hydrophobic lipoproteins, or hydrophilic glycoproteins. The outer membrane contains a variety of lipoproteins and transmembrane outer membrane proteins. Ethanol, alcohol increases levels of high-density lipoproteins (HDLs), which carry cholesterol through the blood. The hydrolyzed VLDL particles are now called VLDL remnants or intermediate-density lipoproteins (IDLs). The envelope of HCV is similar to very-low density lipoproteins (VLDL) and low-density lipoproteins (LDL). They also serve as enzyme cofactors for specific enzymes involved in the metabolism of lipoproteins. This leads to the increased adsorption of hydroxyl groups, lipoproteins, and glycolipids over time. There are various kinds, including glycoproteins and lipoproteins.