1. 1

    Nausea and vomiting (ICD-9 Code 787.01) is one of the top reasons patients see a primary care provider. Infectious diseases causing nausea and vomiting, gastroenteritis, diarrhea, and dehydration are leading causes of death in developing countries, and of sick days and reduction of employee productivity in the United States. Nausea and vomiting postoperatively and during cancer chemotherapy add significant costs, pain, and discomfort to hospital and ambulatory treatment. Dyspepsia occurs in an estimated 25% of the U.S. population every year, many of whom do not seek care. Gaseousness is ubiquitous in the population and is troubling to a small portion.

  2. 2
    Risk Factors

    Previous gastrointestinal surgery, certain medications, chemotherapeutic regimens, substance abuse, pregnancy, infectious diseases, medical conditions, and central nervous system disorders increase the risk for nausea and vomiting symptoms. Dyspepsia risk is increased significantly with ingestion of NSAIDs, tobacco use, H.

    pylori infection, obesity, anxiety, somatization, neuroticism, depression, and unemployment. Increased upper gastrointestinal gaseousness can be seen with air swallowing from gum chewing and eating quickly as well as consumption of foods that relax the lower esophageal sphincter (e.g., chocolate, fats, mints). Ingestion of lactose, fructose, sorbitol, undigested starches (e.g., bran) and carbonated beverages can all increase the risk of bloating and flatulence.

  3. 3

    The pathophysiologic regulation of nausea and vomiting is complex and incompletely understood. Multiple neurotransmitters are involved, including acetylcholine, dopamine, histamine, and serotonin. The therapeutic action of antiemetics is often based on blocking the action of these neurotransmitters. Neurologic regulation of nausea and vomiting involves the chemoreceptor triggers in the fourth ventricle, the nucleus tractus solitarius in the medulla, motor nuclei that control the vomiting reflex, and vagal afferent nerves from the GI tract. The sympathetic and parasympathetic nervous systems are involved in conjunction with the smooth muscle cells and the enteric brain within the wall of the stomach and intestine.

    The pathophysiology of dyspepsia is unclear, but probably has multiple causes. Delayed gastric motility can occur in up to 30% of patients with dyspepsia. Additionally, decreased gastric compliance can be seen in dyspeptic patients.

    Sensations of lower tract gaseousness result from one of three different mechanisms: excess gas production, abnormal intestinal transit, and increased visceral sensitivity. Gas production caused by carbohydrate maldigestion, (e.g., lactose intolerance, poorly absorbed starches) results in bloating and a sensation of fullness. High-fiber diets, celiac disease, and small intestine bacterial overgrowth can increase gas production. Dysmotility associated with diabetes mellitus, scleroderma, amyloidosis, and endocrine disease may result in gastroparesis and chronic intestinal pseudo-obstruction.

    Additionally, previous Nissen fundoplication, fat intolerance, and various familial conditions may cause dysmotility. Increased visceral sensitivity is thought to be a main cause of pain and fullness in patients with functional bowel disorders such as irritable bowel syndrome (IBS) and functional dyspepsia.

  4. 4

    Once the diagnosis has been established, appropriate treatment of the underlying cause of the symptoms can be instituted. When the cause of nausea and vomiting is related to medication, the dose can be adjusted or the medication changed as appropriate.

    Upper GI bloating and fullness is almost exclusively caused by excess air swallow and can be improved with altering behaviors such as gulping food and gum chewing. Lower GI symptoms can be prevented by avoiding problem foods such as milk products in patients with lactose intolerance.

  5. 5
    Clinical Manifestations

    Nausea and vomiting are extremely common and are associated with many conditions. Associated symptoms are helpful in sorting out causes. Many common historical associations are listed in Table 1.

    Table 1
    Key Symptoms and Differential Vomiting, Dyspepsia, and Bloating


    Symptoms                                                                                                                        Differential
    Abdominal Pain ± N/V

    • RUQ

    • Epigastric

    • RLQ

    • LLQ

    • Pelvic

    Organic etiologies

    • Cholelithiasis, cholecystitis

    • Dyspepsia, pancreatitis, GERD, gastritis, MI

    • Appendicitis

    • Diverticulitis

    • PID, ovarian torsion, ectopic pregnancy

    Abdominal pain + distention + N/V Bowel obstruction
    Abdominal distention associated with foods (lactose, wheat-based products, bran, legumes) Lactose intolerance Celiac disease

    Carbohydrate malabsorption, Oligosaccharide  fermentation (legumes)

    Vomiting several hours after eating + succussion splash + N/V Gastric obstruction Gastroparesis
    Heartburn ± N/V GERD, dyspepsia
    Early morning + N/V Pregnancy
    Feculent vomiting + N/V Intestinal obstruction Gastrocolic fistula
    Vertigo + nystagmus + N/V Vestibular neuritis
    Dental erosions, parotid gland enlargement, lanugo-like hair, callus on dorsal surface of hands Bulimia
    Positional N/V Neurogenic

    Abbreviations: GERD = gastroesophageal reflux disease; LLQ = left lower quadrant; MI = myocardial infarction; N/V = nausea and vomiting; PID = pelvic inflammatory disease; RLQ = right lower quadrant; RUQ = right upper  quadrant.

    The diagnosis of dyspepsia is based mainly on clinical symptoms.

    The Rome III criteria are listed in the opening paragraph. Alarm symptoms that should raise suspicions for gastric cancer include unintended weight loss, persistent vomiting, progressive dysphasia, odynophagia, unexplained anemia, iron deficiency, hematemesis, palpable abdominal mass, lymphadenopathy, family history of gastric cancer, previous gastric surgery, or jaundice.

    Gaseousness usually presents with abdominal fullness and bloating.

    Pain associated with the fullness is often relieved with eructation or flatulence (see Table 1).

  6. 6

    The first step in the assessment of patients with abdominal complaints is complete history of the duration of symptoms, the frequency of episodes, work environment, recent travel, household member illness, association of symptoms with certain foods or beverages (i.e., pain relief or worsening with food), and determination of the success or failure of what the patient has tried to alleviate the symptoms, all of which may offer diagnostic clues. Focused inquiries into surgeries, sexual activity, and other elements of a review of symptoms may be helpful. A complete review of medication usage, with particular attention to GI-irritating medications such as NSAIDs and over-the- counter medications, illicit drugs, and herbal products is important.

    Physical examination and diagnostic work-up can help isolate the cause (Table 2).

    Table 2
    Physical Examination: Nausea, Vomiting, Dyspepsia, and Gaseousness

    Findings                                            Possible etiology
    Fever Infectious
    Tachycardia,  hypotension Dehydration, volume depletion, sepsis (infectious), ectopic pregnancy, myocardial infarction, aortic aneurysm
    Exophthalmos Hyperthyroid
    Papilledema Increased intracranial pressure (tumors, subdural hemorrhage)
    Bulging tympanic membrane Otitis media, effusion
    Thyromegaly Hypothyroid
    Lymphadenopathy Infection, malignancy
    Dry mucous membranes Dehydration,  volume depletion
    Dental erosions Bulimia
    Abdominal distention Obstruction, ileus, gastroparesis, irritable bowel, hepatic/spleenic flexure syndrome, postoperative  gas-bloat syndrome
    Absent bowel sounds Ileus, perforation
    Sense of abdominal distention without bloating Irritable bowel syndrome
    Abdominal bloating Irritable bowel syndrome, obstruction
    RUQ  abdominal pain/guarding Cholecysitis, cholelithiasis
    RLQ/LLQ abdominal pain/guarding Appendicitis (RLQ), ovarian torsion, diverticulitis, ectopic pregnancy
    Cervical motion tenderness Pelvic  inflammatory  disease, endometriosis
    Bladder tenderness Urinary tract infection
    Testicular pain Torsion, epididymitis
    Abnormal rectal examination Fecal impaction, prostatitis, appendicitis, ovarian tumor, ectopic pregnancy,
    Delayed cap refill, poor skin turgor Dehydration
    Jaundice Gallbladder disease, biliary obstruction

    Abbreviations: LLQ = left lower quadrant; RLQ = right lower quadrant; RUQ = right upper quadrant.

    In patients with acute (<24 hours) nausea and vomiting, a laboratory workup is often unnecessary. Patients with the most commonly identified acute causes, such as acute gastroenteritis, vestibular neuritis, chemotherapy, medication, and alcohol ingestion, and those who are postoperative, can be started on symptomatic therapy. For persistent symptoms of nausea and vomiting, laboratory workup is guided by the history and physical examination and can include a complete blood count and differential, serum chemistries, renal function, liver function tests, serum protein and albumin, thyroid-stimulating hormone, amylase or lipase, drug screen, and a pregnancy test in women of childbearing age. Imaging should not be routine but should be directed by the history and physical findings as well as pertinent laboratory results. Useful studies may include acute abdominal series (chest x-ray, flat and upright views of the abdomen), abdominal computed tomography (CT), and abdominal ultrasound.

    Similarly, in patients with dyspeptic symptoms, laboratory tests should be obtained based on the history and physical examination. Many therapies, such as discontinuing offending medications (e.g., NSAIDs) or acid suppression in patients without alarm symptoms, may be started without a laboratory work-up. Blood count chemistries and H. pylori testing can be considered if warranted. Alarm symptoms may warrant further imaging or direct visualization with esophagogastroduodenoscopy (EGD).

    In gaseousness and bloating, the most sensitive work-up is the history and physical examination. Further work-up should be directed by initial findings. Patients with alarm symptoms such as weight loss, diarrhea, abdominal pain, distention, and anorexia may benefit from a malabsorption work-up including lactose tolerance test, stool fat, ova and parasites, stool culture, C. difficile, acute abdominal series, or EGD. A hydrogen breath test may be beneficial in selected patients to assess the relationship between specific foods and symptoms. Other blood work, tests, and imaging, such as CT, magnetic resonance imaging (MRI), and EGD are guided by availability of testing and the history, examination and laboratory findings.

    Differential Diagnosis

    Tables 3, 4, and 5 summarize the wide differential diagnosis of nausea and vomiting, dyspepsia, and gaseousness.

    Table 3
    Differential Diagnosis for Nausea and Vomiting

    Central Nervous System

    Multiple sclerosis, tumor, intracranial bleeding, infarction, abscess, meningitis, trauma, labyrinthitis, Ménière’s disease, vestibular neuritis, motion sickness Migraine headaches, seizure disorders Gastrointestinal  Disorders

    Appendicitis, gastric bypass, gastroparesis, hepatobiliary disease cholecystitis, hepatitis, neoplasia Ileus

    Crohn’s disease, ulcerative colitis Irritable bowel syndrome Ischemia: mesenteric, small bowel

    Obstruction: scarring/adhesions from previous surgeries, small bowel obstruction, esophageal spasm Pancreatitis

    Peptic ulcer disease: esophagitis, gastritis, gastroesophageal reflux



    Addison’s disease, diabetes (ketoacidosis, gastroparesis), hyperthyroidism, hypothyroidism, hyperparathyroidism, hypoparathyroidism, porphyria Genitourinary

    Nephritis, nephrolithiasis, torsion (ovary, testicle), uremia, kidney stone

    Infectious Etiologies

    Bacterial: Campylobacter, Salmonella, Shigella,   Enterogenic

    1. coli,

    Viral: rotavirus, influenza Otitis media: bacterial or viral

    Sexually transmitted infection: cervicitis, epididymitis, pelvic inflammatory disease, prostatitis, urethritis; multiple organisms including gonorrhea and chlamydia Urinary tract infection: lower (cystitis) or upper (pyelonephritis)


    Morning sickness, hyperemesis gravidarum, intrauterine and ectopic pregnancies


    Anorexia, anxiety, bulimia, depression

    Medication Related Acetaminophen (Tylenol) Acyclovir (Zovirax) Alcohol abuse

    Antibiotics: azithromycin (Zithromax), sulfasalazine (Azulfidine), erythromycin, metronidazole (Flagyl), sulfonamides (e.g., sulfamethoxazole-trimethoprim [Bactrim]), tetracycline Antidepressants: Selective serotonin reuptake inhibitors (SSRIs) Antihypertensives: β-blockers (atenolol [Tenormin], metoprolol [Lopressor]), calcium channel blockers, diuretics (hydrochlorothiazide)

    Chemotherapeutic agents: cisplatinum (Cisplatin [Platinol]), cyclophosphamide (Cytoxan), nitrogen mustard (Mustargen), dacarbazine (DTIC-Dome), methotrexate (Trexall), vinblastine (Velban)

    Diabetes treatment: metformin (Glucophage), sulfonylureas Digoxin (Lanoxin)

    Ergotamines: dihydroergotamine (Migranal), methysergide (Sansert)2

    Ferrous gluconate, ferrous sulfate Gout treatment: allopurinol (Zylprim)

    Hormones: estrogen, progesterone and oral and injected contraceptives

    Levodopa (L-dopa), carbidopa (Lodosyn)

    Nicotine (patch, gum, smokeless tobacco, cigarette/pipe/cigar) Nonsteroidal antiinflammatory: aspirin, ibuprofen (Motrin), naproxen (Naprosyn)

    Opioids: codeine, heroin, hydrocodone, oxycodone, morphine, burprenorphine/naloxone  (Suboxone)


    Seizure medications: phenobarbital, phenytoin (Dilantin) Theophylline (Uniphyl)

    2  Not available in the United States.

    Table 4
    Differential Diagnosis of Dyspepsia


    Gastrointestinal Disorders

    Functional or nonulcer (most common) Peptic ulcer disease

    Gastoesophogeal reflux Gastritis

    Pancreatitis Gastroparesis Gastric cancer Intestinal ischemia Esophageal rupture Malabsorption Lactase deficiency Celiac


    Parasite infection

    1. H. pylori




    Antibiotics (macrolides and metronidazole) Corticosteroids

    Digoxin Narcotics Theophylline Respiratory Pneumonia Cardiac

    Myocardial ischemia or pericarditis

    Musculoskeletal Abdominal hernia Psychiatric

    Physical sexual abuse

    Abbreviation: NSAIDs = nonsteroidal antiinflammatory  drugs.

    Table 5

    Differential Diagnosis of Bloating and Gaseousness

    Upper GI

    Air swallowing

    Small Bowel

    Pneumatosis cystoides intestinalis Carbohydrate Malabsorption Lactase deficiency

    Legumes (indigestible oligosaccharides) Fructose malabsorption Undigested starch (bran)

    Irritable Bowel Syndrome

    Gas-Producing Foods

    Beans, peas, lentils, broccoli, Brussels sprouts, cauliflower, cabbage, parsnips, leeks, onions, beer, coffee, pork



    Bacterial overgrowth Malabsorption Celiac

    Crohn’s disease

  7. 7

    Antiemetics, hydration, and dietary changes are the first-line treatments for acute episodes of nausea and vomiting. Controlling the symptoms is often all that is necessary in acute, self-limited bouts of nausea and vomiting symptoms. If patients are dehydrated, oral rehydration can be accomplished by encouraging the patient to take small amounts (6 ounces or less) of cool water or electrolyte solutions on a frequent basis. If patients are unable to accomplish this, parenteral rehydration and antiemetics may be warranted.

    Table 6 lists the common antiemetics agents, indications, dosages, side effects, and relative cost of medications.

    Table 6

    Medications for Nausea and Vomiting


    Location of the cause with directed treatment is most effective for gaseousness. If no cause is found, it can be difficult to treat. Avoiding foods that are contributory, such as those containing lactose, fructose, sorbitol, high fiber, and starches, may be all that is necessary.

    Symptoms associated with increased sensitivity to normal levels of gas (i.e., IBS) can be difficult to treat. Therapeutic relationships, education, and dietary modification are the mainstays of IBS treatment. For moderate to severe symptoms, short-term treatment with antispasmotics, tricyclic antidepressants, and antidiarrheal agents may have some benefit. Medical treatments for bloating are listed in Table 7.

    Table 7

    Medications for Treatment of Gaseousness and Bloating

    For most patients with dyspepsia, information can be powerful.

    Validation of symptoms and working toward a goal of management rather than cure are therapeutic. In patients with dyspepsia in which a concern for H. pylori exists, a test-and-treatment strategy can be effective. In other patients, proton pump inhibitors, H-2 receptor antagonists, prokinetic agents, and peppermint oil are all effective short-term therapies.

  8. 8

    For patients who have complications related to nausea and vomiting, monitoring serum electrolytes, renal function, nutritional status, and other parameters may be necessary until hydration improves, electrolytes are replaced, and laboratory results and clinical status return to normal.

    Further testing is needed in patients with dyspepsia and alarm symptoms; however, in patients without alarm symptoms, no further testing is needed.

  9. 9

    The complications of prolonged nausea and vomiting are dehydration, electrolyte disturbances (e.g., hypokalemia, hypophosphatemia and hypomagnesemia), depletion of vitamins and trace elements, metabolic alkalosis, and malnutrition. Usually these can be corrected with oral or intravenous hydration, correction of electrolyte deficiencies, and treatment of the underlying cause. In patients whose nausea and vomiting are accompanied by gastroenteritis, symptoms and clinical status may not return to baseline unless all electrolytes such as potassium, magnesium, phosphorus, and trace elements such as zinc are replaced.

    Dyspeptic patients without alarm symptoms rarely have complications. In patients with chronic bloating, complications are uncommon.

  10. 10

    Abraczinskas D. Intestinal gas and bloating. Available November, 2013 (accessed 6.24.15).

    ACOG Practice Bulletin No. 52: American College of Obstetrics and Gynecology. Nausea and vomiting in pregnancy. Obstet Gynecol. 2004;103:803–814.

    Bailey J. Effective Management of flatulence. Am Fam Phys.


    Flake Z.A., Scalley R.D., Bailey A.G. Practical selection of antiemetics. Am Fam Phys. 2004;69:1169–1174.

    Hasler W.L., Chey W.D. Nausea and vomiting. Gastroenterology.


    Kraft R. Nausea and vomiting. In: Bope E.T., Rakel R.E., Kellerman R., eds. Conn’s Current Therapy 2010. Philadelphia: Saunders; 2010:5–9.

    Longstreth G.F. Functional dyspepsia in adults. Available at December 2014 (accessed 6.24.15).

    Longstreth G.F. Approach to the patient with dyspepsia. Available at September 2014 (accessed 6.24.15).

    Owings S. Gaseousness and dyspepsia. In: Bope E.T., Rakel R.E., Kellerman R., eds. Conn’s Current Therapy 2010. Philadelphia: Saunders; 2010:9–11.

    Talley N.J., Vakil N.B., Moayyedi P. 2005 American Gastroenterological Association technical review on the evaluation of dyspepsia. Gastroenterology. 2005;125:1756–1780.

About Genomic Medicine UK

Genomic Medicine UK is the home of comprehensive genomic testing in London. Our consultant medical doctors work tirelessly to provide the highest standards of medical laboratory testing for personalised medical treatments, genomic risk assessments for common diseases and genomic risk assessment for cancers at an affordable cost for everybody. We use state-of-the-art modern technologies of next-generation sequencing and DNA chip microarray to provide all of our patients and partner doctors with a reliable, evidence-based, thorough and valuable medical service.