Kolliphor EL is an excipient or additive in drugs. It is used as an excipient, and topical ophthalmic protectant and lubricant. Acetone is also present as an excipient in some pharmaceutical drugs. Macrogol is used as an excipient in many pharmaceutical products. The doses of macrogol as an excipient are too low to have relevant contraindications. It is also listed as an approved excipient by the U.S. FDA. Lactitol is listed as an excipient in some prescription drugs. Polysorbate 20 is used as an excipient in pharmaceutical applications to stabilize emulsions and suspensions. It is also used as an excipient in some European and Canadian influenza vaccines. Niosomes are formed mostly by non-ionic surfactant and cholesterol incorporation as an excipient. Other important fields of starch application are textile sizing agents, excipient in tablets for pharmaceuticals. Biological activity of cetalkonium chloride as excipient has been widely described in the scientific literature.