What are the causes of hiccups in the general population?

Causes of Hiccups

Primary Mechanism

Hiccups result from involuntary, erratic contractions of the diaphragm and intercostal muscles followed by sudden laryngeal closure, producing the characteristic "hic" sound. 1 This occurs through disruption of a complex reflex arc involving peripheral phrenic, vagal, and sympathetic pathways with central midbrain modulation. 1

Most Common Causes by Duration

Acute Hiccups (<48 hours)

• Gastric overdistension is the single most common identifiable cause, followed by gastroesophageal reflux disease (GERD) and gastritis. 2
• These episodes are typically benign, self-limited, and resolve spontaneously within minutes. 2

Persistent and Intractable Hiccups (>48 hours)

GERD remains the most common pathological cause of persistent hiccups. 3 Any lesion along the hiccup reflex arc can trigger prolonged episodes. 1

Etiological Categories

Gastrointestinal Causes

• Gastroesophageal reflux disease (most common) 3
• Gastric distension 2
• Gastritis 2
• Esophageal lesions 1

Central Nervous System Causes

• Stroke 1
• Space-occupying lesions (tumors, abscesses) 1
• Traumatic brain injury 1
• Central nervous system infections 1

Peripheral Nerve Irritation

• Lesions affecting the phrenic nerve pathway 1
• Lesions affecting the vagus nerve 1
• Tumors compressing these nerves 1
• Herpes zoster infection 1

Cardiovascular Causes

• Myocardial ischemia 1
• Pericarditis 1

Thoracic/Pulmonary Pathology

• Thoracic tumors 4
• Pulmonary infections 2
• Mediastinal lesions 1

Medication-Induced

• Anti-Parkinsonian drugs 1
• Anesthetic agents 1
• Corticosteroids 1
• Chemotherapy agents 1

Iatrogenic/Procedural

• Medical instrumentation 1
• Post-operative complications 1

Metabolic and Infectious

• Systemic infections 2
• Metabolic derangements 2

Psychogenic

• Psychological disorders can trigger hiccups through central mechanisms 2

Clinical Approach to Diagnosis

For hiccups lasting more than 48 hours or accompanied by weight loss, chest pain, or neurological symptoms, obtain chest X-ray or CT to evaluate for thoracic pathology. 4 A detailed history focusing on medication use, recent procedures, and symptoms suggesting involvement of the reflex arc is essential. 2

First-line investigation should include evaluation for GERD with proton pump inhibitor trial and appropriate gastroenterology consultation, as this represents the most common treatable cause. 3 If gastrointestinal causes are excluded and symptoms persist, investigate central nervous system pathology with neuroimaging. 1

Key Clinical Pitfalls

• Do not dismiss persistent hiccups as benign—they can herald serious underlying pathology including malignancy, stroke, or myocardial ischemia. 2, 1
• Hiccups lasting beyond 48 hours warrant systematic evaluation rather than symptomatic treatment alone. 2
• In patients on chemotherapy or with recent procedural interventions, consider iatrogenic causes before extensive workup. 1