The Green Whistle for Pain Relief

Mar 11, 2022

The Green Whistle for Pain Relief

Australians and New Zealanders have been using the green whistle for over 40 years. But despite its popularity, you may still wonder what is in the green whistle and how it can help trauma victims and medical patients manage their pain.

What is the green whistle and how does it work?

The Penthrox inhaler — or green whistle — is an Australian product that’s quickly becoming an internationally used medical device. It works by delivering small doses of vaporised methoxyflurane via a handheld inhaler to help patients manage pain from trauma or medical procedures.

The green whistle is a unique tool that allows patients to self-administer pain relief. Each dose only lasts around 30 minutes, or until the patient stops using the inhaler, making it an ideal solution for situations that require fast, short-term pain management. So, what’s in a green whistle that makes it so effective?

Penthrox: The green whistle drug

What’s in the green whistle? The answer is methoxyflurane, also commonly known as Penthrox. Methoxyflurane is an inhaled analgesic that appears as a transparent liquid with a distinct, fruity smell.

Methoxyflurane was discovered in the 1960s and used for general anaesthesia until around the 1970s. While countries such as the United States and Canada discontinued the use of methoxyflurane in the 1990s, Australia, New Zealand, and several other countries have continued to use smaller doses of methoxyflurane for pain management and relief.

Penthrox is a non-opioid and is often used as an alternative to analgesics such as morphine or nitrous oxide. While it has a high safety profile, Penthrox is still only recommended for use under direct medical supervision.

What is in the green whistle? Inhaler components

What is in a green whistle device besides Penthrox medicine?
Each green whistle device contains several simple components that allow you to use methoxyflurane safely.

Body and mouthpiece

The body of the green whistle houses a special wick inside and a chamber on top. The patient breathes through a mouthpiece located on one end of the body.

Polypropylene wick

This component is in the body of the whistle. It absorbs the liquid methoxyflurane (which patients add to the body via a one-way valve) and vaporises the liquid so the patient can inhale the vapour.

AC chamber

This small attachment is located on top of the green whistle filled with activated charcoal. The charcoal collects any exhaled methoxyflurane to help prevent other people from being exposed to Penthrox vapour.

Dilutor hole

The dilutor hole is on the AC chamber and allows the patient greater control over their pain management. In addition, covering the hole will create a more potent analgesic effect.

Benefits of the green whistle

The green whistle is a staple analgesic used by paramedics, medical professionals, defence forces and other individuals who work in trauma settings. What makes these devices so popular?

  • Fast-acting. Pain relief can occur quickly after just a few deep breaths with the inhaler. Other analgesics, especially when delivered intravenously, may take longer to work.
  • Easy to use. The green whistle is simple to use and allows the patient to self-medicate as needed.
  • Portable. Unlike other pain relief methods, the green whistle requires no cannula, IV or other equipment to use. It’s compact and portable, making it ideal for a variety of emergencies.
  • Non-addictive. Unlike morphine and other opioids, the green-whistle is not potentially addictive.
  • Limited effects. Once a patient has stopped using the inhaler, the effects of the methoxyflurane disappear within minutes. This can help speed up recovery. Penthrox is also safe to use and has minimal side effects.

Green whistle FAQs

What’s in the green whistle?
The main medicine used in the green whistle is a drug called methoxyflurane, which is also sold as Penthrox. It is an inhaled analgesic that can help with short-term pain management.

Does the green whistle get you high?
No, the green whistle is a non-addictive drug.

Is the green whistle dangerous?
No, not when you follow the dose recommendations. Australians have used the green whistle safely for almost half a century. While high levels of methoxyflurane may lead to serious side effects such as nephrotoxicity and renal failure, the green whistle purposefully provides only low dosages of the drug to prevent these outcomes.

Where to buy a green whistle

Mega Medical is a proud provider of Penthrox products and other medical necessities such as medical gases, emergency oxygen and resuscitation equipment and more. Call us today at 1300 881 824 to purchase Penthrox products for your facility or to learn more about our medical equipment, medical gases, and other services.