Guideline Recommendations for Antibiotic Use and Doxycycline in Chronic Rhinosinusitis

General Principles

Chronic rhinosinusitis (CRS) is fundamentally an inflammatory disease rather than a bacterial infection, and its pathophysiology is driven by immunologic pathways rather than microbial invasion. Strength of evidence: low‑quality systematic reviews. 1

The American Academy of Otolaryngology–Head and Neck Surgery (AAO‑HNS) states that antibiotics should not be prescribed routinely for CRS; they are indicated only when significant purulent nasal discharge is observed on direct examination, indicating an acute bacterial exacerbation. Strength of evidence: consensus guideline (moderate). 1
Systematic reviews cited by the AAO‑HNS show that antibiotic therapy alone achieves clinical success in only about one‑third of CRS cases, reflecting limited and poor‑quality supporting data. Strength of evidence: low. 1
When a bacterial exacerbation is documented, the AAO‑HNS recommends amoxicillin‑clavulanate 875/125 mg twice daily for 10–14 days (or until symptom‑free for 7 days) as the first‑line oral antibiotic regimen. Strength of evidence: moderate (expert consensus). 1

Prolonged doxycycline therapy is not appropriate for routine CRS management; it should be reserved for highly selected, refractory cases after optimization of first‑line therapy. Strength of evidence: low (limited, conflicting data). 1
If doxycycline is considered in a post‑surgical CRS with nasal polyps patient without asthma, non‑steroidal‑exacerbated respiratory disease, or elevated IgE, a regimen of 200 mg on day 1 followed by 100 mg daily for 12 weeks has been used in an open‑label study showing modest improvement in symptom and endoscopic scores. Strength of evidence: low (single prospective study). 1
Adverse‑effect profile of doxycycline (as highlighted by the AAO‑HNS):
Strength of evidence: moderate (well‑documented drug safety data). 1

A 2025 AAO‑HNS meta‑analysis reported that long‑term macrolide therapy (≈3 months) after endoscopic sinus surgery improves postoperative nasal endoscopy scores, but does not produce a significant improvement in patient‑reported quality‑of‑life measures. Strength of evidence: moderate (meta‑analysis). 2
The 2021 AAO‑HNS international consensus group indicated that macrolide antibiotics may be considered as an adjunctive option in CRS, provided that clinicians weigh potential cardiac, gastrointestinal, allergic, and otologic side‑effects. Strength of evidence: moderate (expert consensus). 2

Do not prescribe prolonged antibiotics, including doxycycline, without objective evidence of bacterial infection (purulent discharge). Indiscriminate use offers limited benefit and increases risk of adverse events. Strength of evidence: moderate (guideline recommendation). 1
Do not use antibiotics as first‑line therapy for CRS. Initiate treatment with intranasal corticosteroids and high‑volume saline irrigation before considering any antimicrobial agents. Strength of evidence: strong (clinical practice guideline). 1
Confirm the diagnosis of CRS with objective findings (e.g., nasal endoscopy or CT demonstrating mucosal inflammation persisting >12 weeks) prior to initiating any antibiotic course. Strength of evidence: strong (clinical guideline). 1
Recognize that CRS is not primarily an infectious condition, and the role of bacteria in its initiation or perpetuation remains uncertain, further limiting the justification for routine antibiotic therapy. Strength of evidence: low‑to‑moderate (ongoing debate). 2

The American Academy of Otolaryngology-Head and Neck Surgery recommends that antibiotics should NOT be routinely prescribed for chronic rhinosinusitis (CRS) and should only be used when significant purulent nasal discharge is present on examination, as chronic sinusitis is primarily an inflammatory condition rather than an infectious disease 3
Intranasal corticosteroids and saline irrigation are the cornerstones of chronic sinusitis management, not antibiotics, according to the American Academy of Otolaryngology-Head and Neck Surgery 4
Intranasal corticosteroids should be the first-line therapeutic intervention due to their anti-inflammatory effects and documented efficacy, as suggested by the American Academy of Otolaryngology-Head and Neck Surgery 5
Saline nasal irrigation facilitates mechanical removal of mucus and prevents crusting of secretions, as recommended by the American Academy of Otolaryngology-Head and Neck Surgery 4

The American Academy of Otolaryngology-Head and Neck Surgery recommends that antibiotics should only be prescribed when purulent nasal discharge is present on direct examination 3
If antibiotics are prescribed for documented purulent exacerbations, amoxicillin-clavulanate 875/125 mg twice daily for 10-14 days is the appropriate choice, according to the American Academy of Otolaryngology-Head and Neck Surgery 5
Treatment duration should be 10-14 days or until symptom-free for 7 days, as recommended by the Journal of Allergy and Clinical Immunology 6
Antibiotics should target respiratory anaerobes, viridans streptococci, S. pneumoniae, H. influenzae, and M. catarrhalis, as suggested by the Clinical Infectious Diseases journal 7

The evidence supporting antibiotic use in chronic sinusitis is notably poor, according to the American Academy of Otolaryngology-Head and Neck Surgery 3
Multiple systematic reviews indicate data are limited in quantity and quality, as reported by the American Academy of Otolaryngology-Head and Neck Surgery 3
Conservative therapy with antibiotics alone is successful in only one-third of chronic sinusitis cases, according to the Clinical Infectious Diseases journal 7

Overuse of antibiotics should be avoided unless there is clear evidence of bacterial infection with purulent discharge, as recommended by the American Academy of Otolaryngology-Head and Neck Surgery 3
Indiscriminate antibiotic use is associated with limited efficacy and high potential for side effects, according to the American Academy of Otolaryngology-Head and Neck Surgery 3

Before prescribing antibiotics, confirm the diagnosis with objective documentation of sinonasal inflammation using anterior rhinoscopy, nasal endoscopy, or CT scan, as recommended by the American Academy of Otolaryngology-Head and Neck Surgery 4
Consider short-term oral corticosteroids for marked mucosal edema or treatment failure before adding antibiotics, as suggested by the Journal of Allergy and Clinical Immunology 6