Excipient (pharmacologically inactive substance)
What is it?
Mannitol is a polyol (sugar alcohol) and an isomer of sorbitol. Mannitol (C6H8(OH)6) is used in pharmaceutical products as a sweeting agent, tablet and capsule diluent, excipient for chewable tablets, a tonicity agent, and as a vehicle (bulking agent) for lyophilized preparations. Mannitol is industrially derived from the sugar fructose, and is roughly half as sweet as sucrose. Mannitol has a cooling effect often used to mask bitter tastes, and may be used in gums and candies. Mannitol is also found naturally in many species, including plants, bacteria, and fungi.
Excessive consumption of mannitol may lead to a laxative effect, but the small amount used in pharmaceutical manufacturing processes would not normally pose this risk. Mannitol is deemed a safe food ingredient. Mannitol does not lead to elevated levels of blood sugar, as glucose may, and may be used in the food industry as a sweetener for patients with diabetes. Mannitol contains 1.6 calories per gram. On prescription status, mannitol is used as an intravenous osmotic diuretic and works by increasing the amount of fluid excreted by the body.