Things to Know About Penthrox and How It Works

Jul 14, 2022

Things to Know About Penthrox and How It Works

If you’ve ever spent a significant amount of time in Australia, New Zealand, Ireland or the UK, then you’ve likely heard of the green whistle or Penthrox. But what exactly is Penthrox? Who can use it? And how does it work?

We’re here to answer some of the most common questions regarding Penthrox, methoxyflurane and the green whistle.

Understanding Penthrox

Penthrox is an inhaled analgesic that contains methoxyflurane as an active ingredient. Medical professionals, ambulance services and other medical providers use it to offer pain relief, most commonly to patients who have sustained traumatic injuries or who are undergoing painful procedures. Penthrox’s mechanism of action is the same as that of methoxyflurane, which is described below.

Penthrox inhalers: How to use them

What safety guidelines should you follow if you want to learn how to use Penthrox correctly? Unless you are a medical care provider, you should not attempt to use or administer Penthrox — this drug is a prescription-only medicine. To use your prescribed Penthrox, follow these steps.

  • Step 1: Fill the inhaler by pouring the contents of one Penthrox bottle into the bottom of the inhaler.
  • Step 2: Close the cap and place the wrist loop over your wrist.
  • Step 3: Inhale and exhale gently through the mouthpiece for several seconds to allow yourself to adjust.
  • Step 4: Breathe as you normally would through the inhaler. For more potent pain management, place a finger over the diluter hole on the AC chamber.
  • Step 5: Continue breathing until the pain becomes manageable or until you have reached the maximum recommended dose for the day.
  • Step 6: Dispose of the used inhaler and bottles appropriately.

Penthrox FAQs

What does Penthrox taste like?

The active ingredient in Penthrox — methoxyflurane — has a distinctly fruity smell and a sweet taste.

What are common Penthrox inhaler side effects?

Some of the most common side effects of the green whistle include headaches, nausea, drowsiness or sleepiness, dizziness, coughing and headaches. While less common, more serious adverse effects of Penthrox may include kidney and liver problems, hypotension and malignant hyperthermia.

How long does Penthrox last?

Penthrox is fast-acting but does not linger in your system, which means that its effects will subside shortly after you stop using your inhaler.

Understanding the green whistle

The green whistle is a common name for Penthrox and is so-called because the Penthrox inhaler looks like a green whistle. The device itself is composed of a mouthpiece (through which the patient breathes), a body (into which the patient pours methoxyflurane), and a chamber full of activated charcoal (which traps any unused Penthrox to prevent it from escaping into the air). The inhaler is self-administered and single-use.

Green whistle FAQs

Does the green whistle get you high?

No, you will not get high while using Penthrox. This medication is used to block pain reception rather than cause positive mood changes or decrease inhibitions.
What drug is used in the green whistle?

Penthrox or methoxyflurane is the medication present in the green whistle. This drug is used as a fast-acting, non-opioid analgesic.

Is the green whistle addictive?

No, the drug used in the green whistle is non-addictive, and the pain-relieving effects obtained by using Penthrox will begin to subside soon after a patient stops inhaling the medication.

Understanding methoxyflurane

Methoxyflurane is a volatile anaesthetic used to help reduce or relieve pain in medical situations and emergencies. It has gained popularity in part because methoxyflurane analgesia can help caregivers provide better care and Penthrox is a non-opioid alternative to other traditional pain relief methods.

Penthrox and methoxyflurane are the same thing and can also go by the trade names Penthrop, Penthrane and Metofane.

Methoxyflurane mechanism of action

Penthrox works in the body by influencing membrane fluidity and changing the way ion channels and receptors work, thus helping to inhibit pain and increase muscle relaxation.

Methoxyflurane FAQs

What is methoxyflurane?

Methoxyflurane is one of the more commonly used inhalation anaesthetics. It is a fluorinated hydrocarbon that, when inhaled (usually via Penthrox inhaler), can help reduce or eliminate pain stemming from surgeries, trauma, accidents, etc.

How does methoxyflurane work?

This medication relaxes muscles and reduces pain by inhibiting the central nervous system (the brain and spinal cord) and making the patient less sensitive to pain. It is inhaled via a specially designed inhaler.

Mega Medical: Suppliers of Penthrox and other medical necessities

If you are a medical professional looking to source the green whistle, medical gases, medical equipment or other medical essentials, we can help. As one of Australia’s leading medical equipment suppliers, Mega Medical is uniquely suited to help at-home caregivers, clinics, hospitals and other facilities find the supplies they need to provide superior medical care.

To learn more about our Penthrox inhalers or for help finding additional products, please reach out to us today by calling 1300 881 824.