Bilastine for Sinusitis: Not Recommended
Bilastine (Bilaxten) is not appropriate for treating sinusitis, as there is no evidence supporting antihistamine use in acute bacterial sinusitis, and antihistamines should only be considered if underlying allergic rhinitis is the risk factor for chronic sinusitis. 1
Why Antihistamines Are Not Indicated for Sinusitis
Acute Bacterial Sinusitis
- There are no data presently to recommend the use of H1 antihistamines in acute bacterial sinusitis. 1
- Antihistamines have no antibacterial activity against the causative pathogens (Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis) that drive acute bacterial sinusitis. 2
- The role for antihistamines in sinusitis treatment has not been demonstrated, and they were not recommended in recent guidelines for diagnosis and management of sinusitis. 1
Chronic Sinusitis: Limited Role Only When Allergic Rhinitis Is Present
- There might be a role for antihistamines in chronic sinusitis if the underlying risk factor is allergic rhinitis (AR). 1, 2
- This represents a narrow indication: treating the underlying allergic inflammation that predisposes to recurrent sinus infections, not treating the sinusitis itself. 1
What Bilastine Actually Treats
Allergic Rhinitis (Its Approved Indication)
- Bilastine is a highly selective, non-sedating second-generation H1-antihistamine approved for symptomatic treatment of allergic rhinitis and chronic urticaria. 3, 4, 5
- It demonstrates efficacy comparable to cetirizine and desloratadine in reducing nasal symptoms (rhinorrhea, sneezing, nasal congestion) and ocular symptoms in allergic rhinitis patients. 6, 7, 5
- Bilastine 20 mg once daily significantly improves Total Nasal Symptom Score (TNSS) in perennial allergic rhinitis, with particular effectiveness for sneezing and rhinorrhea. 6, 7
- It has a favorable safety profile with notably less somnolence compared to cetirizine, making it suitable for long-term use. 7, 5
Mechanism and Pharmacology
- Bilastine exhibits rapid onset (within 1 hour) and prolonged duration of action (24 hours), making it appropriate for once-daily dosing. 3, 5
- It does not interact with the cytochrome P450 system and undergoes minimal metabolism, resulting in very low potential for drug-drug interactions. 5
- The drug is excreted largely unchanged and does not require dose adjustment in renal or hepatic impairment. 5
Appropriate Treatment for Sinusitis
Acute Bacterial Sinusitis: First-Line Therapy
- Amoxicillin-clavulanate 875 mg/125 mg twice daily for 5-10 days is the preferred first-line antibiotic for acute bacterial sinusitis. 2
- High-dose amoxicillin-clavulanate (2 g/125 mg twice daily) should be used for patients with recent antibiotic use, age >65 years, moderate-to-severe symptoms, or comorbid conditions. 2
Diagnostic Criteria Before Prescribing Antibiotics
- Antibiotics should only be prescribed when acute bacterial sinusitis is confirmed by one of three patterns: 2
- Persistent symptoms ≥10 days without clinical improvement
- Severe symptoms (fever ≥39°C with purulent discharge) for ≥3 consecutive days
- "Double sickening" (worsening after initial improvement from viral URI)
Essential Adjunctive Therapies
- Intranasal corticosteroids (mometasone, fluticasone, or budesonide twice daily) are strongly recommended as adjunctive therapy in both acute and chronic sinusitis. 2
- Saline nasal irrigation provides symptomatic relief and improves antibiotic penetration. 8, 2
- Analgesics (acetaminophen or ibuprofen) for pain and fever management. 2
When Bilastine Might Be Considered (Indirectly)
Chronic Sinusitis with Underlying Allergic Rhinitis
- If a patient has chronic or recurrent sinusitis (≥3 episodes per year) with documented allergic rhinitis as the underlying risk factor, treating the allergic rhinitis with bilastine may help reduce sinus inflammation and prevent recurrent infections. 1, 2
- However, this represents treatment of the predisposing condition (allergic rhinitis), not treatment of active sinusitis. 1
- Patients with chronic or recurrent sinusitis should be evaluated for underlying allergic rhinitis, immunodeficiency, and anatomic abnormalities. 2
Critical Pitfalls to Avoid
- Never use bilastine or any antihistamine as monotherapy for acute bacterial sinusitis, as it lacks antibacterial activity and will not address the underlying infection. 1
- Do not prescribe antibiotics for viral rhinosinusitis lasting <10 days unless severe symptoms are present, as 98-99.5% of acute rhinosinusitis is viral and resolves spontaneously. 2
- Antihistamines are less effective for nasal congestion than for other nasal symptoms, and other options are generally better choices for more severe allergic rhinitis. 1
- Because antihistamines are generally ineffective for nonallergic rhinitis, other choices are typically better for mixed rhinitis. 1