What causes left-sided throat pain and how is it treated?

Left-Sided Throat Pain: Causes and Treatment

Immediate Clinical Assessment

Left-sided throat pain requires urgent evaluation to exclude life-threatening conditions, particularly if accompanied by fever, difficulty swallowing, or respiratory symptoms. 1, 2

Red Flags Requiring Emergency Evaluation

• Peritonsillar abscess: Unilateral tonsillar swelling, uvular deviation away from the affected side, trismus (difficulty opening mouth), "hot potato voice," and severe dysphagia 1
• Retropharyngeal abscess: Neck stiffness, posterior pharyngeal wall swelling, drooling, and difficulty swallowing 1
• Epiglottitis: Drooling, stridor, sitting forward position, and respiratory distress—airway management is paramount 1, 2
• Lemierre syndrome: Severe pharyngitis in adolescents/young adults with high fever and septic appearance, which can progress to life-threatening septic thrombophlebitis of the internal jugular vein 1, 3

Common Non-Emergent Causes

For isolated left-sided throat pain without red flags, the most likely causes are:

• Viral pharyngitis (most common): Self-limited, resolves within 7 days, associated with cough, rhinorrhea, and low-grade fever 1, 4
• Group A Streptococcal pharyngitis: Assess using Centor criteria (tonsillar exudates, tender anterior cervical lymphadenopathy, fever >38°C, absence of cough) 5, 6
• Chemical/irritant pharyngitis: Immediate onset after exposure to acidic foods/beverages, tobacco smoke, or environmental irritants 7
• Gastroesophageal reflux disease (GERD): Chronic throat irritation without classic heartburn, particularly if symptoms persist beyond 2 weeks 1

Chronic Presentations (>2 weeks)

Symptoms persisting beyond 2 weeks require evaluation for serious non-infectious causes, particularly malignancy in older adults, and empiric antibiotics are not indicated. 1

• Malignancy: Critical diagnosis in elderly patients with isolated persistent unilateral symptoms 1
• Tonsillar or oropharyngeal cancer: Unilateral persistent pain, especially in patients with tobacco/alcohol use 8

Diagnostic Approach

When to Test for Streptococcal Infection

Use Centor criteria to guide testing decisions: 5, 6

• 0-2 criteria: No testing needed, antibiotics not indicated 5, 7
• 3-4 criteria: Consider rapid antigen detection test (RADT); throat culture not necessary after negative RADT 5

Centor criteria components: 5

• Tonsillar exudates
• Tender anterior cervical lymphadenopathy
• Fever (history of temperature >38°C)
• Absence of cough

When NOT to Test

• Chronic presentations (>2 weeks)—clinical scoring systems are not validated for chronic symptoms 1
• Presence of viral symptoms (cough, rhinorrhea, conjunctivitis) 4

Treatment Recommendations

Pain Management (First-Line)

Ibuprofen 400-600 mg every 6-8 hours or acetaminophen 500-1000 mg every 6 hours are recommended as first-line therapy for symptom relief. 6, 7

• Ibuprofen is more effective than acetaminophen for throat pain 9
• Avoid aspirin in children due to Reye syndrome risk 6
• Exercise caution with NSAIDs in elderly patients due to cardiovascular, renal, and gastrointestinal risks 1

Adjunctive Symptomatic Measures

• Warm salt water gargles for temporary relief 6, 7
• Topical anesthetics (lozenges containing benzocaine or lidocaine) for temporary relief 6
• Adequate hydration with neutral pH fluids 7

Antibiotic Therapy

Antibiotics should NOT be prescribed for most cases of acute sore throat. 5, 1

Indications for antibiotics (if streptococcal infection confirmed or highly suspected): 5, 6

• 3-4 Centor criteria with positive RADT or in high-prevalence settings
• First choice: Penicillin or amoxicillin for 5-7 days 5, 4
• Alternative: Clarithromycin if penicillin allergy 4

Antibiotics provide only modest symptom reduction (approximately 16 hours shorter duration) and should not be used to prevent complications in low-risk patients. 5, 4

Corticosteroids

Corticosteroids are NOT routinely recommended for streptococcal pharyngitis. 6

• The Infectious Diseases Society of America explicitly recommends against corticosteroids as adjunctive therapy (weak recommendation, moderate quality evidence) 6
• Minimal benefit (approximately 5 hours pain reduction) does not outweigh potential adverse effects 6
• May be considered in adults with severe presentations (3-4 Centor criteria) in conjunction with antibiotics, but this is not routine practice 5

Common Pitfalls to Avoid

• Do not prescribe empiric antibiotics without identifying the underlying cause or assessing streptococcal risk 1, 7
• Do not continue standard acute pharyngitis management beyond 2 weeks without investigating alternative diagnoses 1
• Do not rely solely on nitroglycerin response as a diagnostic criterion—relief with nitroglycerin is not specific for cardiac ischemia and throat pain can be an atypical presentation of acute coronary syndrome in elderly patients, women, and diabetics 5
• Do not miss serious diagnoses by failing to perform indirect laryngoscopy when oropharyngeal examination is normal despite severe pain 8