He may suffering form gastritis, due gastritis vomiting, due to vomiting he may goes into dehydration. so he need intra venous fluids antacids, and antibiotics and antiemitcs. Gastritis can be caused by irritation due to excessive alcohol use, chronic vomiting, stress, or the use of certain medications such as aspirin or other anti-inflammatory drugs. It may also be caused by any of the following: Helicobacter pylori (H. pylori): A bacteria that lives in the mucous lining of the stomach. Bile is a greenish-yellow fluid that is essential for digesting fats and for eliminating worn-out red blood cells and certain toxins from your body. Bile is produced in your liver and stored in your gallbladder. Magnesium-containing antacids may cause diarrhea. People with certain kidney problems should use these cautiously or not at all. Aluminum-containing antacids can cause constipation. Antiemetics: Antiemetic medications help control nausea and vomiting. A number of different antiemetics can be used to control gastritis symptoms. Some of these medications are available by prescription for home use as well. Note that these medications do not improve the gastritis, but rather only decrease the symptoms of gastritis. Fluid replacement is the treatment for dehydration. This may be attempted by replacing fluid by mouth, but if this fails, intravenous fluid (IV) may be required. Should oral rehydration be attempted, frequent small amounts of clear fluids should be used.