Functional Gastrointestinal Disorders

Symptoms without a structural or tissue abnormality. Diagnosis is based on symptoms, with tests and investigations only if the patient has features that warrant further work-up.

Includes: functional heartburn, functional dyspepsia, belching, hiccups, cyclical vomiting (below), gastroparesis, irritable bowel syndrome, functional bloating, functional diarrhoea, functional constipation (see Constipation).

Belching

Generally caused by habitual ingestion of air (aerophagia). Made worse by GORD and functional dyspepsia — also causes excessive gastric rumbling (borborygmi), and sometimes excessive flatus.

Management: reassure patients. Consider a speech pathology referral if supragastric belching.

Hiccups

Acute severe hiccups: investigate the underlying cause (e.g. diaphragmatic irritation).

Chronic idiopathic hiccups are distressing and difficult to manage. Consider dopamine antagonists — metoclopramide, haloperidol, or chlorpromazine — or baclofen/gabapentin. Stimulation of the soft palate with a wet cotton bud for 1 minute can be effective.

Cyclical vomiting

Severe, unexplained nausea and vomiting occurring in an otherwise healthy individual at varying intervals — a variant of migraine. Episodes last hours to days; common in children around age 5, with associated photophobia, abdominal pain, or headache. Usually remits in adulthood.

Indications for investigation

• Family history of bowel cancer or coeliac disease.
• Onset of symptoms at age >50.
• Significant weight loss (~5–10%).
• Dysphagia.
• Severe, large-volume diarrhoea.
• Steatorrhoea.
• Persistent vomiting.
• Severe abdominal pain.
• Fever.
• Symptoms that interfere with sleep.
• Anaemia.
• Evidence of GI bleeding (rectal bleeding, haematemesis, positive FOBT).
• Abdominal examination abnormality.
• Inflammation on blood tests or stool samples.