Mannitol is a white, crystalline sugar alcohol with the chemical formula (C6H8(OH)6). It is used as an osmotic diuretic agent and a weak renal vasodilator. It was originally isolated from the secretions of the flowering ash and called manna after its resemblance to the Biblical food. It is also referred to as mannite and manna sugar. In plants, it is used to induce osmotic stress.