A type of sugar often used as medication, it’s primary use is as a sweetener for diabetic as it has a poor rate of absorption in the digestive tract. In medication form, mannitol is used to decrease high pressure in the eyes particularly with treating glaucoma. It is also used to induce a drop in intracranial pressure, and is typically administered via injection. As it is primarily an osmotic diuretic, mannitol functions by pulling fluid directly from the brain and the eyes. Effects usually manifest within 15 minutes, and can last for up to 8 hours. Side effects include electrolyte deficiency and dehydration. There is also evidence that it may worsen heart failure and increase the rate of kidney failure in some cases.The effects of using Mannitol during pregnancy are also unknown.