A 2002 systemic review of herbal products found that several herbs, including peppermint and caraway, have anti-dyspeptic effects for non-ulcer dyspepsia with "encouraging safety profiles". A 2004 meta-analysis of the multiple herbal extract Iberogast found it to be more effective than placebo in people with functional dyspepsia.

Antacids and sucralfate were found to be no better than placebo in a literature review. H2-RAs have been shown to have marked benefit in poor quality trials (30% relative risk reduction), but only a marginal benefit in good quality trials. Prokinetic agents would empirically seem to work well since delayed gastric emptying is considered a major pathophysiological mechanism in functional dyspepsia. They have been shown in a meta-analysis to produce a relative risk reduction of up to 50%, but the studies evaluated to come to this conclusion used the drug cisapride which has since been removed from the market (now only available as an investigational agent) due to serious adverse events such as torsades, and publication bias has been cited as a potential partial explanation for such a high benefit. Modern prokinetic agents such as metoclopramide, erythromycin and tegaserod have little or no established efficacy and often result in substantial side effects. Simethicone has been found to be of some value, as one trial suggests potential benefit over placebo and another shows equivalence with cisapride. So, with the somewhat recent advent of the proton pump inhibitor (PPI) class of medications, the question of whether these new agents are superior to traditional therapy has arisen.

Currently, PPIs are, depending on the specific drug, FDA indicated for erosive esophagitis, gastroesophageal reflux disease (GERD), Zollinger-Ellison syndrome, eradication of H. pylori, duodenal and gastric ulcers, and NSAID-induced ulcer healing and prevention, but not functional dyspepsia. There are, however, evidence-based guidelines and literature that evaluate the use of PPIs for this indication. A helpful chart summarizing the major trials is available from the functional dyspepsia guidelines published in the World Journal of Gastroenterology in 2006.

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.

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.

There is considerable research into the causes, diagnosis and treatments for FGIDs. Diet, microbiome, genetics, neuromuscular function and immunological response all interact. Heightened mast cell activation has been proposed to be a common factor among FGIDs, contributing to visceral hypersensitivity as well as epithelial, neuromuscular, and motility dysfunction.

Gastrointestinal diseases refer to diseases involving the gastrointestinal tract, namely the esophagus, stomach, small intestine, large intestine and rectum, and the accessory organs of digestion, the liver, gallbladder, and pancreas.

A Low FODMAP diet now has an evidence base sufficiently strong to recommend its widespread application in conditions such as IBS and IBD. Restriction of Fermentable Oligo-, Di- and Mono-

saccharides and Polyols globally, rather than individually, controls the symptoms of functional gut disorders (e.g. IBS), and the majority of IBD patients respond just as well. It is more successful than restricting only Fructose and Fructans, which are also FODMAPs, as is recommended for those with Fructose malabsorption. Longer term compliance with the diet was high.

A randomised controlled trial on IBS patients found relaxing an IgG-mediated food intolerance diet led to a 24% greater deterioration in symptoms compared to those on the elimination diet and concluded food elimination based on IgG antibodies may be effective in reducing IBS symptoms and is worthy of further biomedical research.

Intestinal or bowel hyperpermeability, so called leaky gut, has been linked to food allergies and some food intolerances. Research is currently focussing on specific conditions and effects of certain food constituents. At present there are a number of ways to limit the increased permeability, but additional studies are required to assess if this approach reduces the prevalence and severity of specific conditions.

Some individuals may benefit from diet modification, such as a reduced fat diet, following cholecystectomy. The liver produces bile and the gallbladder acts as reservoir. From the gallbladder, bile enters the intestine in individual portions. In the absence of gallbladder, bile enters the intestine constantly, but in small quantities. Thus, it may be insufficient for digestion of fatty foods. Postcholecystectomy syndrome treatment depends on the identified violations that led to it. Typically, the patient is recommended dietary restriction table with fatty foods, enzyme preparations, antispasmodics, sometimes cholagogue.

If the pain is caused by biliary microlithiasis, oral ursodeoxycholic acid can alleviate the condition.

A trial of bile acid sequestrant therapy is recommended for bile acid diarrhoea.

Functional gastrointestinal disorders (FGID) include a number of separate idiopathic disorders which affect different parts of the gastrointestinal tract and involve visceral hypersensitivity and impaired gastrointestinal motility.

Even though anatomically part of the GI tract, diseases of the mouth are often not considered alongside other gastrointestinal diseases. By far the most common oral conditions are plaque-induced diseases (e.g. gingivitis, periodontitis, dental caries). Some diseases which involve other parts of the GI tract can manifest in the mouth, alone or in combination, including:

- Gastroesophageal reflux disease can cause acid erosion of the teeth and halitosis.

- Gardner's syndrome can be associated with failure of tooth eruption, supernumerary teeth, and dentigerous cysts.

- Peutz–Jeghers syndrome can cause dark spots on the oral mucosa or on the lips or the skin around the mouth.

- Several GI diseases, especially those associated with malabsorption, can cause recurrent mouth ulcers, atrophic glossitis, and angular cheilitis (e.g. Crohn's disease is sometimes termed orofacial granulomatosis when it involves the mouth alone).

- Sideropenic dysphagia can cause glossitis, angular cheilitis.

Surgical intervention is nearly always required in form of exploratory laparotomy and closure of perforation with peritoneal wash. Occasionally they may be managed laparoscopically.

Conservative treatment including intravenous fluids, antibiotics, nasogastric aspiration and bowel rest is indicated only if the person is nontoxic and clinically stable.

Gastrointestinal perforation, also known as ruptured bowel, is a hole in the wall of part of the gastrointestinal tract. The gastrointestinal tract includes the esophagus, stomach, small intestine, and large intestine. Symptoms include severe abdominal pain and tenderness. When the hole is in the stomach or early part of the small intestine the onset of pain is typically sudden while with a hole in the large intestine onset may be more gradual. The pain is usually constant in nature. Sepsis, with an increased heart rate, increased breathing rate, fever, and confusion may occur.

The cause can include trauma such as from a knife wound, eating a sharp object, or a medical procedure such as colonoscopy, bowel obstruction such as from a volvulus, colon cancer, or diverticulitis, stomach ulcers, ischemic bowel, and a number of infections including "C. difficile". A hole allows intestinal contents to enter the abdominal cavity. The entry of bacteria results in a condition known as peritonitis or in the formation of an abscess. A hole in the stomach can also lead to a chemical peritonitis due to gastric acid. A CT scan is typically the preferred method of diagnosis; however, free air from a perforation can often be seen on plain X-ray.

Perforation anywhere along the gastrointestinal tract typically requires emergency surgery in the form of an exploratory laparotomy. This is usually carried out along with intravenous fluids and antibiotics. A number of different antibiotics may be used such as piperacillin/tazobactam or the combination of ciprofloxacin and metronidazole. Occasionally the hole can be sewn closed while other times a bowel resection is required. Even with maximum treatment the risk of death can be as high as 50%. A hole from a stomach ulcer occurs in about 1 per 10,000 people per year, while one from diverticulitis occurs in about 0.4 per 10,000 people per year.

Postcholecystectomy syndrome describes the presence of abdominal symptoms after surgical removal of the gallbladder (cholecystectomy), 2 years after the surgery.

Symptoms of postcholecystectomy syndrome may include:

- Dyspepsia, nausea, and vomiting.

- Flatulence, bloating, and diarrhea.

- Persistent pain in the upper right abdomen.

Symptoms occur in about 5 to 40 percent of patients who undergo cholecystectomy, and can be transient, persistent or lifelong. The chronic condition is diagnosed in approximately 10% of postcholecystectomy cases.

The pain associated with postcholecystectomy syndrome is usually ascribed to either sphincter of Oddi dysfunction or to post-surgical adhesions. A recent study shows that postcholecystectomy syndrome can be caused by biliary microlithiasis.

Approximately 50% of cases are due to biliary causes such as remaining stone, biliary injury, dysmotility, and choledococyst. The remaining 50% are due to non-biliary causes. This is because upper abdominal pain and gallstones are both common but are not always related.

Chronic diarrhea in postcholecystectomy syndrome is a type of bile acid diarrhea (type 3). This can be treated with a bile acid sequestrant like cholestyramine, colestipol or colesevelam, which may be better tolerated.

There is emerging evidence from studies of cord bloods that both sensitization and the acquisition of tolerance can begin in pregnancy, however the window of main danger for sensitization to foods extends prenatally, remaining most critical during early infancy when the immune system and intestinal tract are still maturing. There is no conclusive evidence to support the restriction of dairy intake in the maternal diet during pregnancy in order to prevent. This is generally not recommended since the drawbacks in terms of loss of nutrition can out-weigh the benefits. However, further randomised, controlled trials are required to examine if dietary exclusion by lactating mothers can truly minimize risk to a significant degree and if any reduction in risk is out-weighed by deleterious impacts on maternal nutrition.

A Cochrane review has concluded feeding with a soy formula cannot be recommended for prevention of allergy or food intolerance in infants. Further research may be warranted to determine the role of soy formulas for prevention of allergy or food intolerance in infants unable to be breast fed with a strong family history of allergy or cow's milk protein intolerance. In the case of allergy and celiac disease others recommend a dietary regimen is effective in the prevention of allergic diseases in high-risk infants, particularly in early infancy regarding food allergy and eczema. The most effective dietary regimen is exclusively breastfeeding for at least 4–6 months or, in absence of breast milk, formulas with documented reduced allergenicity for at least the first 4 months, combined with avoidance of solid food and cow's milk for the first 4 months.

There is insufficient evidence to recommend the use of any herbal or dietary supplements for treating dysmenorrhea, including, melatonin, vitamin E, fennel, dill, chamomile, cinnamon, damask rose, rhubarb, guava, and uzara. Further research is recommended to follow up on weak evidence of benefit for: fenugreek, ginger, valerian, zataria, zinc sulphate, fish oil, and vitamin B1. A 2016 review found that evidence of safety is insufficient for all dietary supplements.

There is some conflicting evidence in the scientific literature, including:

One review found thiamine and vitamin E to be likely effective. It found the effects of fish oil and vitamin B12 to be unknown.

Reviews found tentative evidence that ginger powder may be effective for primary dysmenorrhea.

Another review found Vitamin B1 to be effective. Magnesium supplementation are a promising possible treatment.

Reviews have found promising evidence for Chinese herbal medicine for primary dysmenorrhea, but that the evidence was limited by its poor methodological quality.

Nonsteroidal anti-inflammatory drugs (NSAIDs) are effective in relieving the pain of primary dysmenorrhea. They can have side effects of nausea, dyspepsia, peptic ulcer, and diarrhea. People who are unable to take the more common NSAIDs may be prescribed a COX-2 inhibitor.

Treatment may involve investigation, reassurance and explanation, and possibly specialist treatment such as antidepressants or cognitive behavioral therapy.

Functional somatic syndromes may occur in 6 to 36% of the population.

Another method for increasing absorption through the ileum is to ingest a Cbl complex to which IF is already bound. The lack of intrinsic factor produced by the patient's body can be supplemented by using synthetic human IF produced from pea plant recombinants. However, in cases where IF-antibodies are the reason for malabsorption across the ileum, this treatment would be ineffective.

Sublingual treatments have also been postulated to be more effective than oral treatments alone. A 2003 study found, while this method is effective, a dose of 500 μg of cyanocobalamin given either orally or sublingually, is equally efficacious in restoring normal physiological concentrations of cobalamin. Intranasal methods have also been studied as a vehicle for the delivery of cobalamin. A 1997 study monitored the plasma cobalamin concentration of six patients with pernicious anemia over a period of 35 days while being treated with 1500 μg of intranasal hydroxocobalamin. One hour after administration, all patients showed on average an immediate eight-fold increase in plasma cobalamin concentration and a two-fold increase after 35 days with three 1500 μg treatments. However, further studies are needed to investigate the long-term effectiveness of this delivery method.

Medium-term (and less well-demonstrated) treatments of hypotension include:

- Blood sugar control (80–150 by one study)

- Early nutrition (by mouth or by tube to prevent ileus)

- Steroid support

Beard, with his partner A.D. Rockwell, advocated first electrotherapy and then increasingly experimental treatments for people with neurasthenia, a position that was controversial. An 1868 review posited that Beard's and Rockwell's knowledge of the scientific method was suspect and did not believe their claims to be warranted.

William James was diagnosed with neurasthenia, and was quoted as saying, "I take it that no man is educated who has never dallied with the thought of suicide."

In 1895, Sigmund Freud reviewed electrotherapy and declared it a "pretense treatment." He emphasized the example of Elizabeth von R's note that "the stronger these were the more they seemed to push her own pains into the background."

Nevertheless, neurasthenia was a common diagnosis during World War I for "shell shock", but its use declined a decade later. Soldiers who deserted their post could be executed even if they had a medical excuse, but officers who had neurasthenia were not executed.

The treatment for hypotension depends on its cause. Chronic hypotension rarely exists as more than a symptom. Asymptomatic hypotension in healthy people usually does not require treatment. Adding electrolytes to a diet can relieve symptoms of mild hypotension. A morning dose of caffeine can also be effective. In mild cases, where the patient is still responsive, laying the person in dorsal decubitus (lying on the back) position and lifting the legs increases venous return, thus making more blood available to critical organs in the chest and head. The Trendelenburg position, though used historically, is no longer recommended.

Hypotensive shock treatment always follows the first four following steps. Outcomes, in terms of mortality, are directly linked to the speed that hypotension is corrected. Still-debated methods are in parentheses, as are benchmarks for evaluating progress in correcting hypotension. A study on septic shock provided the delineation of these general principles. However, since it focuses on hypotension due to infection, it is not applicable to all forms of severe hypotension.

1. Volume resuscitation (usually with crystalloid)

2. Blood pressure support with a vasopressor (all seem equivalent with respect to risk of death, with norepinephrine possibly better than dopamine). Trying to achieve a mean arterial pressure (MAP) of greater than 70 mmHg does not appear to result in better outcomes than trying to achieve a MAP of greater than 65 mm Hg in adults.

3. Ensure adequate tissue perfusion (maintain SvO2 >70 with use of blood or dobutamine)

4. Address the underlying problem (i.e., antibiotic for infection, stent or CABG (coronary artery bypass graft surgery) for infarction, steroids for adrenal insufficiency, etc...)

The best way to determine if a person will benefit from fluids is by doing a passive leg raise followed by measuring the output from the heart.

Where an underlying cause can be identified, treatment may be directed at this. Clearly heavy periods at menarche and menopause may settle spontaneously (the menarche being the start and menopause being the cessation of periods).

If the degree of bleeding is mild, all that may be sought by the woman is the reassurance that there is no sinister underlying cause. If anemia occurs due to bleeding then iron tablets may be used to help restore normal hemoglobin levels.

The condition is often treated with hormones, particularly as abnormal uterine bleeding commonly occurs in the early and late menstrual years when contraception is also sought. Usually, oral combined contraceptive or progesterone only pills may be taken for a few months, but for longer-term treatment the alternatives of injected Depo Provera or the more recent progesterone releasing IntraUterine System (IUS) may be used. Fibroids may respond to hormonal treatment, and if they do not, then surgical removal may be required.

Tranexamic acid tablets that may also reduce loss by up to 50%. This may be combined with hormonal medication previously mentioned.

Anti-inflammatory medication like NSAIDs may also be used. NSAIDs are the first-line medications in ovulatory menorrhagia, resulting in an average reduction of 20-46% in menstrual blood flow. For this purpose, NSAIDs are ingested for only 5 days of the menstrual cycle, limiting their most common adverse effect of dyspepsia.

A definitive treatment for menorrhagia is to perform hysterectomy (removal of the uterus). The risks of the procedure have been reduced with measures to reduce the risk of deep vein thrombosis after surgery, and the switch from the front abdominal to vaginal approach greatly minimizing the discomfort and recuperation time for the patient; however extensive fibroids may make the womb too large for removal by the vaginal approach. Small fibroids may be dealt with by local removal (myomectomy). A further surgical technique is endometrial ablation (destruction) by the use of applied heat (thermoablation).

In the UK the use of hysterectomy for menorrhagia has been almost halved between 1989 and 2003. This has a number of causes: better medical management, endometrial ablation and particularly the introduction of IUS which may be inserted in the community and avoid the need for specialist referral; in one study up to 64% of women cancelled surgery.

Aside from the social distress of dealing with a prolonged and heavy period, over time the blood loss may prove to be greater than the body iron reserves or the rate of blood replenishment, leading to anemia. Symptoms attributable to the anemia may include shortness of breath, tiredness, weakness, tingling and numbness in fingers and toes, headaches, depression, becoming cold more easily, and poor concentration.