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Recruiting NCT07295054

3 mL Inhaled Methoxyflurane for Intrauterine Device (IUD) Insertion

Phase IV Interventional IUD

For patients and families

In plain language

An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.

What is being studied
The protocol lists: Methoxyflurane, Saline.
Who it may be relevant to
Registry conditions: IUD. Basic parameters: 18 years — 55 years · Female.
What needs checking
Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
Where it takes place
Canada
Next step
Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →

Unsure about the terms? Read our patient guide →

Official title

A Double-blind Placebo-controlled Randomized Controlled Trial (RCT) of 3 mL Inhaled Methoxyflurane for Intrauterine Device (IUD) Insertion

Overview

Intrauterine device (IUD) insertion is a common contraceptive procedure often associated with moderate to severe pain, particularly among nulliparous individuals. Current pain management strategies, such as over-the-counter analgesics, are frequently inadequate. Methoxyflurane, a short-acting, self-administered inhaled analgesic, has been shown to provide rapid and effective pain relief in acute and procedural settings. This study aims to evaluate whether 3 mL of inhaled Methoxyflurane (via Penthrox inhaler) improves patient satisfaction by reducing pain and anxiety during IUD insertion.

Detailed description

Methoxyflurane is a short-acting, self-administered inhaled analgesic that has demonstrated rapid and effective pain relief in acute trauma, emergency, and procedural settings. It is non-narcotic, allows patients to control dosing, and does not require intravenous access or prolonged recovery, making it suitable for short outpatient procedures. Existing studies indicate that Methoxyflurane provides faster onset of pain relief compared to standard analgesics, is generally well-tolerated, and has only transient, non-serious adverse effects such as dizziness or headache.

This study aims to evaluate the efficacy of 3 mL of inhaled Methoxyflurane, delivered via Penthrox inhaler, in reducing pain and anxiety during IUD insertion. The primary objective is to assess patient satisfaction with pain management. Secondary outcomes include procedural pain scores, anxiety levels, and the incidence of adverse events. This trial seeks to provide evidence for an effective, safe, and patient-centered approach to pain management during IUD insertion, potentially improving patient experience and access to long-acting contraceptive options.

Interventions

  • Drug Methoxyflurane
    3 mL of Methoxyflurane via a handheld inhaler
  • Drug Saline
    3 mL of Normal Saline via an identical placebo handheld inhaler

Primary outcome measures

  • Procedural pain intensity [Time frame: 20 minutes after post-procedure]
Secondary outcome measures (9)
  • Patient-centered measure of satisfaction with procedural sedation [Time frame: 20 minutes after post procedure]
  • Patient satisfaction with pain management [Time frame: Baseline before procedure]
  • Patient distress [Time frame: Pre-procedure and post procedure 0,20 minutes and 24 hours.]
  • Patient Anxiety [Time frame: Pre-procedure and post procedure 0,20 minutes and 24 hours.]
  • Recall peak pain during procedure [Time frame: 0 minutes after post procedure]
  • Provider-centered measure of satisfaction with procedural sedation [Time frame: 20 minutes after post procedure]
  • Assess the effectiveness of blinding [Time frame: 20 minutes after post procedure]
  • Symptom Reporting / Emergency Visits [Time frame: 24 hours after post procedure]
  • Patient Satisfaction with Pain Management [Time frame: 20 minutes after post procedure]

Eligibility criteria

Inclusion criteria

  • Patients with a uterus.
  • Ages 18 to 55 years.
  • Undergoing any intrauterine device (IUD) insertion.
  • English-speaking participants.
  • Ability to use an inhaler device.
  • Willing to receive a cervical block for their IUD insertion

Exclusion criteria

  • Inability to provide informed consent.
  • Confirmed pregnancy.
  • Use of pain medication other than NSAIDs or acetaminophen (e.g., opioids, benzodiazepines, muscle relaxants) within 24 hours prior to the intervention.
  • Use of cannabis within 24 hours prior to the intervention.
  • Administration of misoprostol within 24 hours prior to the intervention.
  • Altered level of consciousness due to any cause, including head injury, drugs, or alcohol.
  • History of severe adverse reactions to Penthrox (methoxyflurane) or other halogenated anesthetic agents, or to any ingredient in the formulation (including non-medicinal ingredients or container components).
  • Anatomical variance, such as distorted uterine cavity, bicornuate uterus, uterus didelphys, or cervical stenosis.
  • Clinically significant renal and/or liver impairment.
  • Known or genetic susceptibility to malignant hyperthermia.
  • Clinically evident hemodynamic or cardiovascular instability, or respiratory depression.
  • Not NPO according to hospital guidelines.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation
Randomized
Model
Parallel assignment
Masking
Triple blind
Primary purpose
Treatment

Study locations

Canada · 1 center
  • Women's College Hospital — Toronto

Identifiers

NCT: NCT07295054 · 2025-0056-B

Primary sources (government registries)

View this study on ClinicalTrials.gov ↗