There are many tools for investigating stomach problems. The most common is endoscopy. This procedure is performed as an outpatient and utilizes a small flexible camera. The procedure does require intravenous sedation and takes about 30–45 minutes; the endoscope is inserted via the mouth and can visualize the entire swallowing tube, stomach and duodenum. The procedure also allows the physician to obtain biopsy samples. In many cases of bleeding, the surgeon can use the endoscope to treat the source of bleeding with laser, clips or other injectable drugs.

Smoking has been linked to a variety of disorders of the stomach. Tobacco is known to stimulate acid production and impairs production of the protective mucus. This leads to development of ulcers in the majority of smokers.

Chronic stomach problems have also been linked to excess intake of alcohol. It has been shown that alcohol intake can cause stomach ulcer, gastritis and even stomach cancer. Thus, avoidance of smoking and excess alcohol consumption can help prevent the majority of chronic stomach disorders.

One of the most causes of chronic stomach problems is use of medications. Use of aspirin and other non-steroidal anti-inflammatory drugs to treat various pain disorders can damage lining of the stomach and cause ulcers. Other medications like narcotics can interfere with stomach emptying and cause bloating, nausea, or vomiting.

The majority of chronic stomach problems are treated medically. However, there is evidence that a change in life style may help. Even though there is no specific food responsible for causing chronic stomach problems, experts recommend eating a healthy diet which consists of fruits and vegetables. Lean meat should be limited. Moreover, people should keep a diary of foods that cause problems and avoid them.

Hyperchlorhydria, sometimes called chlorhydria, refers to the state in the stomach where gastric acid levels are higher than the reference range. The combining forms of the name ("" + ""), referring to chlorine and hydrogen, are the same as those in the name of hydrochloric acid, which is the active constituent of gastric acid.

In humans, the normal pH is around 1 to 3, which varies throughout the day. The highest basal secretion levels are in the late evening (around 12 A.M. to 3 A.M.). Hyperchlorhydria is usually defined as having a pH less than 2. It has no negative consequences unless other conditions are also present such as gastroesophageal reflux disease (GERD).