Mannitol in the clinical use is very wide, like can be used to treat brain diseases, as well as the use of diuretic effect to reduce intracranial pressure, intraocular pressure; as well as auxiliary treatment of diseases such as nephropathy, cirrhosis of the liver and ascites; and drug overdose or drug toxicity, the use of mannitol can play a role in accelerating the role of the kidneys to excrete. The price of mannitol is usually the current specification is 250ml/bottle at about 5 dollars, because different manufacturers produce may be price discrepancies, so buy to the actual pharmacy and hospital prices prevail. Although widely used, but any drug also has side effects, mannitol is no exception. Mannitol’s side effects are mainly after a large number of injections, which can lead to a rapid increase in the body’s blood volume, thus triggering heart failure; there are also some patients who will have an allergic reaction. Therefore, to apply mannitol, it is recommended that it is best to apply it under the guidance of a professional doctor.