What is the role of intranasal glucocorticosteroids (e.g., fluticasone propionate (Flonase)) in treating sinus infections?

Intranasal Corticosteroids for Sinus Infections

Intranasal corticosteroids (such as fluticasone propionate) should be used as adjunctive therapy to antibiotics in acute bacterial sinusitis and as first-line monotherapy for chronic rhinosinusitis, as they provide modest but clinically meaningful symptom relief by reducing inflammation in the sinonasal mucosa. 1, 2

Evidence for Use in Different Types of Sinusitis

Acute Sinusitis

• When combined with antibiotics, intranasal corticosteroids provide significantly greater symptom reduction compared to antibiotics alone, particularly for inflammatory symptoms like headache, facial pain, and nasal congestion 3, 4
• The evidence shows that 73% of patients receiving intranasal corticosteroids experience resolution or improvement of symptoms versus 66.4% with placebo (risk ratio 1.11,95% CI 1.04 to 1.18) 4
• Treatment duration for acute sinusitis is typically 15-21 days 3, 4

Chronic Rhinosinusitis

• Intranasal corticosteroids are recommended as the most effective medication class for controlling major symptoms including nasal congestion, rhinorrhea, and inflammation 1, 2
• Long-term treatment reduces inflammation, decreases nasal polyp size, and improves nasal blockage, rhinorrhea, and loss of smell 5
• For chronic rhinosinusitis without improvement after 3 months of intranasal corticosteroids, consider adding a short course (5-7 days) of oral corticosteroids 1

Mechanism of Action

• Intranasal corticosteroids work by decreasing vascular permeability, inhibiting release of inflammatory mediators (histamine, leukotrienes, prostaglandins, cytokines), and reducing inflammatory cell infiltration, particularly eosinophils 6, 1
• Unlike oral antihistamines that only block histamine, intranasal corticosteroids act on multiple inflammatory pathways, which explains their superior efficacy for nasal congestion 7
• Although intranasal corticosteroids may not directly reach the interior of the paranasal sinuses, their anti-inflammatory effect on the nasal mucosa and ostia makes them effective adjunctive therapy 6, 1

Dosing Recommendations

Adults and Children ≥12 Years

• Standard dose: 2 sprays per nostril once daily (e.g., fluticasone propionate 200 mcg total daily dose) 7
• Higher doses (400 mcg twice daily for mometasone furoate) show stronger symptom improvement but increased epistaxis risk 3, 8
• Maximum duration before physician consultation: 6 months of continuous daily use 7

Children Ages 4-11 Years

• Lower dose: 1 spray per nostril once daily 7
• Maximum duration: 2 months per year before physician consultation due to potential effects on growth rate 1, 7
• When used long-term, intranasal glucocorticoids may slow growth rate in some children, though effects on ultimate adult height remain unknown 1

Administration Technique (Critical for Efficacy)

• Direct the spray away from the nasal septum to minimize local side effects such as nasal irritation, bleeding, and septal perforation 1, 2
• Prime the pump before first use and after periods of non-use to ensure full dose delivery 7
• Continue using daily as long as exposed to allergens, even after symptoms improve 7
• Periodically examine the nasal septum to ensure no mucosal erosions 1, 2

Safety Profile

Local Adverse Effects

• Epistaxis (nosebleeds) is the most common adverse effect, occurring more frequently with higher doses (risk ratio 2.06,95% CI 1.20 to 3.54) 8
• Most epistaxis is mild (streaks of blood in mucus) and rarely requires discontinuation 8
• Local irritation may occur but is generally well-tolerated 6

Systemic Effects

• When used at recommended doses, intranasal corticosteroids are not associated with clinically significant systemic side effects 1, 2
• Less than 1% of fluticasone propionate is systemically available after intranasal administration 9
• Unlike topical decongestants, intranasal corticosteroids do not cause rhinitis medicamentosa (rebound congestion) and can be used long-term 6, 2

Drug Interactions

• Consult physician before use if taking:
  • HIV protease inhibitors (e.g., ritonavir) - may increase fluticasone levels 7
  • Ketoconazole (oral antifungal) - may increase fluticasone levels 7
  • Other systemic corticosteroids for asthma, allergies, or other conditions - to monitor total steroid burden 7

Common Pitfalls and Clinical Pearls

• Failure to use proper spray technique is the most common reason for treatment failure - ensure patients understand to aim away from the septum 1, 2
• Patients often discontinue therapy prematurely when symptoms improve - counsel that continued use is necessary to maintain symptom control during allergen exposure 7
• It may take several days to reach maximum effect, so set appropriate expectations for symptom relief timeline 7
• Do not use for common cold symptoms - intranasal corticosteroids are only effective for allergic rhinitis and sinusitis, not viral upper respiratory infections 7
• Intranasal corticosteroids should be continued postoperatively in patients who undergo endoscopic sinus surgery 1
• If no improvement after 3-4 weeks of appropriate therapy, refer to a specialist for further evaluation 1, 2

When to Consider Oral Corticosteroids

• Short courses (5-7 days) of oral corticosteroids may be added for:
  • Severe chronic rhinosinusitis with nasal polyps 1, 2
  • Marked mucosal edema 1
  • Failure to respond to intranasal corticosteroids and antibiotics 1
• Use oral corticosteroids cautiously due to potential systemic side effects 2

Combination Therapy Approach

• For enhanced effectiveness, combine intranasal corticosteroids with saline nasal irrigation 1
• Antibiotics should only be added when bacterial infection is confirmed, with minimum 3-week course for chronic infectious sinusitis 1
• Do not routinely add antihistamines - they have side effects and do not effectively relieve sinusitis symptoms unless allergic rhinitis is also present 6, 2