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Potent Topical Corticosteroid (Nasal Drops) Pregnancy: Caution — systemic betamethasone absorbed; avoid prolonged use especially in first trimester; saline drops preferred in pregnancy where possible

Betamethasone Sodium Phosphate Nasal Drops

Brand names: Betnesol Drops (0.1%)

Adult dose

Dose: 2–3 drops into each nostril twice daily (0.1% solution); use in head-down position
Route: Intranasal drops
Frequency: Twice daily
Max: 6 drops per nostril per day
For nasal polyp reduction — more potent and penetrates higher than sprays; apply in head-down and forward position (head over bed or prayer position) to allow drops to reach polyp region; typically 4-6 week courses; higher systemic absorption than nasal sprays

Paediatric dose

Dose: 1–2 drops per nostril twice daily (specialist use only) drops/kg
Route: Intranasal
Frequency: Twice daily
Max: 4 drops per nostril per day
Paediatric use specialist only due to systemic absorption risk

Dose adjustments

Renal

No dose adjustment required

Hepatic

No dose adjustment required

Paediatric weight-based calculator

Paediatric use specialist only due to systemic absorption risk

Clinical pearls

  • Drops vs sprays for nasal polyposis: drops deliver medication higher into the nasal cavity (reaching the ethmoid and sphenopalatine regions where polyps originate) than standard nasal sprays, which coat the anterior septum — superior distribution achieved with correct head position
  • Head position technique is critical: patient must be in head-down position (vertex to ground) — either kneeling with forehead on floor, over the edge of a bed, or using a nasal douche position; without correct positioning, drops pool in the pharynx rather than reaching polyps
  • Systemic absorption higher than nasal sprays: betamethasone drops have significant systemic bioavailability (~50%) compared to modern nasal sprays (<1% for mometasone/fluticasone furoate) — limit course length, monitor for systemic steroid effects, avoid in children without specialist supervision
  • Pre-operative polyp reduction: Betnesol drops commonly used for 4-6 weeks before functional endoscopic sinus surgery (FESS) to shrink polyps, improve surgical field, and reduce intraoperative bleeding
  • Biologic era context: for patients failing drops + surgery, biologic therapy (dupilumab, mepolizumab, omalizumab) is now NICE-approved — betamethasone drops remain first-line medical management before biologic qualification

Contraindications

  • Untreated nasal infections (fungal, viral, bacterial)
  • Known hypersensitivity to betamethasone

Side effects

  • Nasal dryness/crusting
  • Epistaxis
  • HPA axis suppression (greater risk than nasal sprays — systemic absorption higher with drops)
  • Nasal septal perforation (prolonged use)
  • Candidiasis (rare)

Interactions

  • Systemic corticosteroids — additive HPA suppression
  • CYP3A4 inhibitors (itraconazole, ritonavir) — increase betamethasone systemic exposure

Monitoring

  • Nasal endoscopy (polyp response)
  • Systemic steroid effects if prolonged (blood pressure, glucose)
  • HPA axis if long courses (early morning cortisol)
  • Epistaxis frequency

Reference: BNFc; BNF 90; NICE CKS Nasal Polyps; BAO-HNS Guideline for Rhinosinusitis (2016); EPOS 2020; SPC Betnesol Drops. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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