Persistent nausea or vomiting

The possible diagnoses for a patient presenting with persistent nausea and/or vomiting are many and varied but can often be considered under five main headings:

• Pregnancy.

• Visceral disease.

• Toxic substance effects/metabolic conditions.

• Central nervous system disease.

• Psychiatric illness.

Assessment of the patient

Assessment of the patient with persistent nausea and vomiting should fall into two categories:

• Assessment of the physical state of the patient, which has occurred as a consequence of the nausea/vomiting.

• Look for evidence of:
  

  • Poor nutritional state

  • Dehydration

  • Electrolyte imbalance

• Assessment of the patient with regard to the potential underlying cause.

Pregnancy

• Nausea and vomiting of pregnancy affects nearly 75% of pregnant women¹ .

• About 1% of women develop hyperemesis gravidarum, which may result in adverse outcomes for the mother and fetus.

• Also consider the following:

  • Morning sickness.

  • Urinary tract infection.

  • Reflux oesophagitis.

  • Mechanical pressure from the gravid uterus.

Common causes of persistent nausea and vomiting

Visceral disease

• Reflux oesophagitis or gastro-oesophageal reflux disease (GORD).

• Obstruction - eg, due to malignancy or chronic constipation.

• Cholecystitis.

• Hepatitis.

• Urinary tract infection.

• Gastroparesis - delayed gastric emptying.

Toxic substance effects/metabolic conditions

• Drugs - eg, cytotoxic agents, erythromycin, digoxin toxicity, theophylline.

• Alcohol.

• Hypercalcaemia.

• Uraemia.

• Diabetic ketoacidosis.

Central nervous system disease

• Cyclical vomiting syndrome - this is characterised by recurrent, discrete episodes of vomiting in an otherwise healthy person, usually a child² . It can also be associated with episodes of abdominal pain and there is often a family history of migraines.

• Vestibular labyrinthitis and Ménière's disease.

• Raised intracranial pressure - eg, due to a space-occupying lesion, intracranial bleed.

Psychiatric disease

• Bulimia nervosa.

• Functional.

• Psychogenic.

Investigations

Full history

It is important to pay particular attention to duration, severity, aggravating and relieving factors, associated features, drug and occupational history, social history, last menstrual period, previous medical history and recent trauma.

Full examination

In particular, assess hydration and nutritional state, examine the abdomen, sclera and optic discs and check for nystagmus.

The following tests may be appropriate:

• Urine dipstick - for protein, blood, glucose, pH, bilirubin, urobilinogen.

• Serum urea.

• Serum calcium.

• LFTs.

• FBC.

• Pregnancy test.

• Abdominal X-ray.

• Abdominal ultrasound.

• Endoscopy.

• Abdominal CT/MRI scan.

• CT or MRI of the brain if there is suspicion of raised intracranial pressure.

Nausea management

General measures

• Patients with persistent nausea and/or vomiting should be given appropriate dietary advice and advice on fluid intake.

• Patients with severe dehydration may require treatment with intravenous fluids.

• Psychiatric or psychology referral may be appropriate for those thought to have an underlying psychiatric/psychological cause.

• Pregnant women should be given emotional support, advice concerning diet and adequate nutritional intake and be advised to avoid large-volume meals and tight clothing. See the separate Nausea and Vomiting in Pregnancy article for more information.

• There is some evidence for the use of acupuncture for the symptomatic relief of nausea and vomiting and this may be an option for some patients. A Cochrane review found low-quality evidence to support its use in the prevention of postoperative nausea and vomiting³ .

Pharmacological

• Once the cause of vomiting has been established, symptomatic relief may be given (if appropriate) in the form of antiemetic therapy.

• Many classes of drugs exhibit antiemetic properties - eg, antihistamines, phenothiazines (such as prochlorperazine) and antipsychotic drugs (such as haloperidol).

• Metoclopramide acts directly on the gastrointestinal tract. However, there is a risk of potentially serious neurological adverse effects with this drug, such as extrapyramidal disorders and tardive dyskinesia.

• In view of these potential adverse effects, the following restrictions to indications, dose and duration of use of metoclopramide have been made⁴ :
  

  • In adults over 18 years, metoclopramide should only be used for prevention of postoperative nausea and vomiting, radiotherapy-induced nausea and vomiting, delayed (but not acute) chemotherapy-induced nausea and vomiting, and symptomatic treatment of nausea and vomiting, including that associated with acute migraine (where it may also be used to improve absorption of oral analgesics).

  • It should only be prescribed for short-term use (up to five days).

  • Oral liquid formulations should be given via an appropriately designed, graduated oral syringe to ensure dose accuracy.

• Medications including cyclizine and metoclopramide have been shown to be safe and effective treatments in pregnancy⁵ .

• Domperidone acts at the chemoreceptor trigger zone and is especially useful for nausea and vomiting associated with chemotherapy.

• Prokinetic agents such as domperidone can also be beneficial in the management of those with gastroparesis⁶ .

• Gastro-electrical stimulation is an option for treating chronic, intractable nausea and vomiting secondary to gastroparesis⁷ .

• Granisetron and ondansetron are specific 5HT₃ antagonists and, as such, are particularly useful for postoperative nausea and vomiting and that associated with cytotoxic therapy. They can also be beneficial in children⁸ . A Cochrane review could not identify any antiemetic regime that was superior to any other⁹ .

• Dexamethasone and nabilone (a synthetic cannabinoid) may be useful for patients on cytotoxic drugs, with nausea that is resistant to other therapy.

Surgical

Surgery may be required to treat some underlying causes of nausea and vomiting - eg, raised intracranial pressure and some forms of obstruction.

Nausea and vomiting complications

Recurrent vomiting may result in:

• Dehydration

• Electrolyte disturbance

• Oesophagitis/gastritis

• Mallory-Weiss syndrome