People are usually advised to avoid foods that bother them.Gastritis is believed to affect about half of people worldwide. In 2013 there were approximately 90 million new cases of the condition. As people get older the disease becomes more common. It, along with a similar condition in the first part of the intestines known as duodenitis, resulted in 50,000 deaths in 2015. H. pylori was first discovered in 1981 by Barry Marshall and Robin Warren. Signs and symptoms
Many people with gastritis experience no symptoms at all. However, upper central abdominal pain is the most common symptom; the pain may be dull, vague, burning, aching, gnawing, sore, or sharp. Pain is usually located in the upper central portion of the abdomen, but it may occur anywhere from the upper left portion of the abdomen around to the back. Other signs and symptoms may include the following:

Nausea
Vomiting (may be clear, green or yellow, blood-streaked or completely bloody depending on the severity of the stomach inflammation)
Belching (does not usually relieve stomach pain if present)
Bloating
Early satiety
Loss of appetite
Unexplained weight loss

Causes
There are two categories of gastritis depending on the cause of the disease. There is erosive gastritis, for which the common causes are stress, alcohol, some drugs, such as aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs), and Crohns disease. And, there is non-erosive gastritis, for which the most common cause is a Helicobacter pylori infection.
Physostigmine (also known as eserine from éséré, the West African name for the Calabar bean) is a highly toxic parasympathomimetic alkaloid, specifically, a reversible cholinesterase inhibitor. It occurs naturally in the Calabar bean and the fruit of the Manchineel tree. The chemical was synthesized for the first time in 1935 by Percy Lavon Julian and Josef Pikl. It is available in the U.S. under the trade names Antilirium and Isopto Eserine, and as eserine salicylate and eserine sulfate. Today, physostigmine is most commonly used for its medicinal value. However, before its discovery by Sir Robert Christison in 1846, it was much more prevalent as an ordeal poison. The positive medical applications of the drug were first suggested in the gold medal-winning final thesis of Thomas Richard Fraser at the University of Edinburgh in 1862. Medical uses
Physostigmine is used to treat glaucoma and delayed gastric emptying. Because it enhances the transmission of acetylcholine signals in the brain and can cross the blood–brain barrier, physostigmine salicylate is used to treat anticholinergic poisoning (that is, poisoning by substances that interfere with the transmission of acetylcholine signaling, such as atropine, scopolamine, and other anticholinergic drug overdoses). It is also used to reverse neuromuscular blocking. Physostigmine is the antidote of choice for Datura stramonium poisoning. It is also an antidote for Atropa belladonna poisoning, the same as for atropine. It has also been used as an antidote for poisoning with GHB, but is poorly effective and often causes additional toxicity, so is not a recommended treatment.