Mannitol in combination with dexamethasone has the potential to exacerbate chronic gastritis. 1.Mannitol: Mannitol is commonly used in the treatment of various causes of cerebral edema, reduce intracranial pressure, renal tubular necrosis, etc., but also for the adjunctive treatment of nephrotic syndrome, cirrhosis ascites and other diseases, also has a certain auxiliary role. However, some patients can also experience gastrointestinal symptoms such as nausea and vomiting when using mannitol intravenous drip. 2. Dexamethasone: Dexamethasone belongs to hormone drugs, with anti-inflammatory, anti-allergic, anti-shock effect, commonly used in allergic diseases, autoimmune diseases and other treatments. But in the process of using the drug may cause irritation to the gastrointestinal tract, nausea, vomiting, peptic ulcer and so on. For those suffering from chronic gastric inflammation, due to long-term stimulation of the gastric mucosa, it is possible to cause nausea, vomiting and other gastrointestinal symptoms. To summarize, both mannitol and dexamethasone may cause gastrointestinal symptoms, so it is possible that chronic gastritis will be aggravated when the two drugs are used in combination. Mannitol and dexamethasone need to be used under the guidance of a doctor, and in the process of treatment of symptoms of discomfort, it is recommended to consult a doctor in a timely manner.