Comparing Penthrox to placebo for pain relief in sinus procedures

The Effectiveness of Inhaled Methoxyflurane (Penthrox) vs Placebo for Pain Relief in Coblation and Sinus Procedures: a Double-blind, Randomized, Placebo - Controlled Trial

PHASE1; PHASE2 · St. Paul's Hospital, Canada · NCT06750302

This study is testing if inhaling Penthrox can help people feel less pain during minor sinus procedures compared to a placebo.

Quick facts

PhasePHASE1; PHASE2
Study typeInterventional
Enrollment100 (estimated)
Ages19 Years and up
SexAll
SponsorSt. Paul's Hospital, Canada (other)
Locations1 site (Vancouver, British Columbia)
Trial IDNCT06750302 on ClinicalTrials.gov

What this trial studies

This randomized, double-blind, placebo-controlled trial evaluates the effectiveness of inhaled methoxyflurane (Penthrox) as an analgesic for patients undergoing minor sinus and rhinology procedures, such as Endoscopic Sinus Surgery (ESS) and coblation. Participants will inhale either Penthrox or a placebo during their procedure and will be assessed for pain relief using the Visual Analog Scale (VAS), as well as for anxiety and complications. The study aims to determine if Penthrox provides superior pain relief compared to placebo, potentially improving patient comfort during these procedures.

Who should consider this trial

Good fit: Ideal candidates for this study are adults aged 19 years or older scheduled for minor sinus surgery or coblation procedures.

Not a fit: Patients with conditions such as cystic fibrosis, severe kidney or liver disease, or those with a history of respiratory depression may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could provide a non-invasive and effective pain management option for patients undergoing minor sinus procedures.

How similar studies have performed: Previous studies have shown promising results for methoxyflurane in acute pain management, but its use in minor surgical procedures is less explored, making this approach somewhat novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Age 19 years or older
* Scheduled for minor sinus surgery or coblation procedures

Exclusion Criteria:

* Cystic fibrosis
* Systemic vasculitis or other bleeding disorders
* History of renal failure or severe kidney disease
* History of liver failure or severe liver disease
* Altered state of consciousness (head injury, alcohol use, drug use)
* Known or suspected hypersensitivity to lidocaine or sensorcaine
* Inhaled drug use (i.e., cocaine) in the preceding 6 months
* Nasal tumors
* Personal or family history of malignant hyperthermia
* Respiratory depression

Where this trial is running

Vancouver, British Columbia

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Chronic Rhinosinusitis, Sinus Surgery, Endoscopic Sinus Surgery, Coblation, Methoxyflurane, Penthrox, Inhaled Analgesic, Inhaled Analgesics in Rhinology

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.