Use of Inhaled Vapour (Penthrox™) for Painful Procedures

Everyone experiences pain differently. For some medical procedures, over-the-counter pain relief may not be enough. Penthrox™ is one option that may help. Talk to your provider about what’s right for you.

• Can be used by healthy adults between the ages of 18 and 65
• Can be self-administered
• Commonly called the “green whistle”
• Pain relief typically starts within five minutes. Continuous use provides relief for 25-30 minutes, while intermittent use may last up to 60 minutes.
• Penthrox^TM can be used with acetaminophen (Tylenol^TM).                 

What is Penthrox^TM? 

• Penthrox^TM (generic name is methoxyflurane) is an inhaled vapour medication used for short-term pain relief during medical procedures.
• It is commonly called the “green whistle” due to the shape and color of the handheld  inhaler. 
• It is self-administered; you breathe in and out through the device after receiving instructions on how to use it.
• Pain relief typically starts within five minutes. Continuous use provides relief for 25-30 minutes, while intermittent use may last up to 60 minutes. 
• Penthrox^TM can be used with acetaminophen (Tylenol^TM). 

Who can use it? 

• Healthy adults between the ages of 18 and 65.

Do not use Penthrox if

• You have trouble breathing or feel unwell
• You or family member had anesthesia reaction (e.g., malignant hyperthermia)
• You have kidney/liver disease
• You are pregnant or breastfeeding
• You take narcotics, sedatives, muscle relaxants, antihistamines, or certain antibiotics.
• You drank alcohol recently.
• You used Penthrox™ in the last 48 hours or multiple times in 3 months
• You had a negative experience with Penthrox™ before