What are the causes of unilateral epistaxis (nosebleed in one nostril)?

Causes of Epistaxis in One Nostril Only

Unilateral epistaxis is commonly caused by localized factors such as trauma, inflammation, or vascular abnormalities in the affected nostril, requiring targeted examination and treatment based on the specific underlying cause.

Common Causes of Unilateral Epistaxis

• Local trauma: Digital manipulation (nose picking), nasal foreign bodies, or direct injury to one side of the nose 1, 2
• Mucosal dryness and inflammation: Localized drying of nasal mucosa in one nostril, often exacerbated by dry environments, heating systems, or nasal oxygen use 1, 2
• Septal abnormalities: Deviated septum causing airflow changes and dryness on one side 3, 2
• Vascular abnormalities: Prominent blood vessels in Kiesselbach's plexus (anterior nasal septum) on the affected side 2
• Localized infection: Rhinosinusitis affecting one side of the nasal cavity 1, 3

Less Common but Important Causes

• Nasal tumors: Benign or malignant growths that can present with unilateral epistaxis 2
• Vascular malformations: Localized telangiectasias or arteriovenous malformations 1, 3
• Hereditary hemorrhagic telangiectasia (HHT): Though often bilateral, can present initially with unilateral bleeding 1, 2
• Intranasal drug use: Topical medication overuse or illicit drug snorting affecting one nostril 1, 4
• Post-surgical changes: Previous nasal or sinus surgery affecting one side 1

Systemic Factors That Can Present as Unilateral Bleeding

• Anticoagulant/antiplatelet medications: May cause bleeding that manifests in one nostril first 1, 4
• Coagulation disorders: Bleeding disorders may initially present with unilateral epistaxis 1, 2
• Hypertension: Can exacerbate bleeding from a pre-existing vulnerable vessel on one side 1, 2

Diagnostic Approach for Unilateral Epistaxis

• Anterior rhinoscopy: Essential first step to identify the bleeding site after removal of any blood clots 1
• Nasal endoscopy: Recommended for persistent unilateral epistaxis to thoroughly examine the nasal cavity and identify posterior bleeding sources 1, 3
• Assessment of risk factors: Document factors that increase bleeding severity including medication use, bleeding disorders, and intranasal drug use 1

Red Flags for Unilateral Epistaxis

• Persistent unilateral bleeding: May indicate underlying pathology requiring further investigation 3
• Recurrent bleeding from the same nostril: Suggests a specific anatomical or vascular abnormality 3, 2
• Associated symptoms: Nasal obstruction, facial pain, or visual changes with unilateral epistaxis may suggest a mass lesion 1
• Severe bleeding: Unilateral epistaxis with duration >30 minutes in a 24-hour period requires prompt medical attention 3

Management Considerations for Unilateral Epistaxis

• Targeted treatment: Direct interventions to the specific bleeding site in the affected nostril 1
• Nasal compression: Apply firm sustained compression to the lower third of the nose for at least 5 minutes 1
• Cauterization: When a specific bleeding site is identified, restrict cautery only to the active site in the affected nostril 1
• Topical vasoconstrictors: Can be applied to the affected nostril to reduce bleeding 1, 5
• Nasal packing: Consider resorbable packing for patients with bleeding disorders or on anticoagulation therapy 1

Prevention of Recurrent Unilateral Epistaxis

• Nasal moisturization: Regular application of saline sprays and lubricating agents to prevent mucosal dryness 3
• Humidification: Use of humidifiers in dry environments to maintain nasal mucosal health 3
• Avoidance of trauma: Patient education about avoiding digital manipulation of the affected nostril 3, 2
• Management of underlying conditions: Treat local infections, allergies, or systemic factors contributing to unilateral bleeding 1, 2