Imagine an emergency room where a patient’s lungs have completely shut down, the ventilator is maxed out, and the usual backup machines aren’t available. Instead of giving up, doctors reach for an unexpected, science-fiction–sounding option: delivering oxygen through the gut—sometimes nicknamed “butt breathing.”

It sounds wild, maybe even a little uncomfortable to think about, but the idea is rooted in solid biology. Certain animals can absorb oxygen through their intestines, and scientists in Japan and elsewhere are now testing whether a carefully engineered version of this could one day help humans survive catastrophic respiratory failure.

Illustration of experimental gut-based oxygen delivery as a backup for failing lungs
Experimental “butt breathing” techniques aim to deliver oxygen through the intestine when lungs can no longer do the job. Image © Daily Galaxy / source photo credit as cited by the original publisher.

Why Are Scientists Even Considering “Butt Breathing”?

The core problem is simple and serious: when lungs fail, our options are limited. During crises like severe pneumonia, acute respiratory distress syndrome (ARDS), COVID-19, or major trauma, people may become so oxygen-starved that:

  • Mechanical ventilators (breathing machines) are no longer enough.
  • Advanced support like ECMO (a heart–lung bypass machine) is unavailable or too risky.
  • Patients in low-resource settings may not have access to high-tech devices at all.

In these extreme situations, doctors sometimes have nothing left to offer. That’s what drives the search for an emergency “backup port” for oxygen—somewhere else in the body where oxygen can be safely and effectively absorbed.


The Science Behind Intestinal “Butt Breathing”

The technical name for this idea is intestinal respiratory support or enteral ventilation. It’s inspired by animals that can absorb oxygen through their guts, including:

  • Some fish and amphibians, which can take up oxygen through their intestines when in low-oxygen water.
  • Certain turtles, which famously use cloacal respiration—absorbing oxygen near the tail end of the gut.

Human intestines are highly vascular, meaning they’re packed with blood vessels. They already absorb nutrients and medications into the bloodstream. The question researchers asked is: can they also absorb enough oxygen to matter in an emergency?

“Our experiments show that intestinal delivery of oxygen can rescue mice and pigs from otherwise lethal levels of oxygen deprivation. This suggests a possible path to emergency respiratory support when conventional options are exhausted.”
— Adapted from early preclinical research reports in major peer-reviewed journals

In animal studies, scientists tested two main approaches:

  1. Oxygen-rich liquids: Special perfluorocarbon-based liquids can carry large amounts of dissolved oxygen. When gently infused into the rectum and lower intestine of animals, they were able to:
    • Raise blood oxygen levels.
    • Improve survival under otherwise lethal low-oxygen conditions.
  2. Oxygen gas delivery: Under very controlled conditions, small amounts of oxygen gas were also tested, though this raises more safety concerns and is currently less favored.

These experiments are still early, but they laid the groundwork for carefully monitored, small-scale human safety studies now underway in Japan and other research centers.


How Would Gut Oxygen Delivery Work in an Emergency?

The vision—still experimental—looks something like this in a hospital setting:

  1. Stabilization first: The patient is already receiving standard care: oxygen, mechanical ventilation, and circulatory support.
  2. Assessment: Doctors determine that:
    • The lungs can’t provide enough oxygen despite maximal support.
    • ECMO or other advanced options are unavailable, too risky, or have failed.
  3. Catheter placement: A soft, flexible tube is inserted into the rectum, similar to how certain medical enemas or rectal medications are given.
  4. Infusion of oxygen-rich fluid: A carefully warmed, sterile, oxygen-loaded liquid is slowly infused into the lower intestine.
  5. Monitoring: Blood oxygen saturation, blood pressure, heart rate, and organ function are monitored continuously.
  6. Temporary bridge: If effective and safe, this method might:
    • Raise blood oxygen just enough to prevent organ failure.
    • Buy time until lungs recover or ECMO becomes available.

What Does the Evidence Actually Show So Far?

As of late 2025, here’s a grounded look at where the science stands:

  • Animal studies: In mice and pigs placed in severe low-oxygen conditions:
    • Intestinal oxygen delivery increased blood oxygen saturation.
    • Some animals survived conditions that were otherwise uniformly fatal.
    • Careful preparation of the intestinal lining (sometimes including gentle abrasion in early animal work) improved oxygen absorption—but such invasive steps are not appropriate for humans.
  • Early human safety trials: Small, closely supervised studies in Japan have focused on:
    • Whether people can safely tolerate oxygen-rich liquids in the rectum and lower intestine.
    • Short-term side effects like discomfort, inflammation, or changes in vital signs.
    • Initial signals of improved blood oxygen levels in controlled conditions.
  • No large-scale clinical use—yet: This is still far from routine hospital practice. There are no approved “butt breathing” devices for emergency use at this time.

Researchers emphasize that this method is a potential adjunct—a tool to be added on top of existing respiratory support in very specific emergencies, not a shortcut for chronic lung disease or lifestyle-related breathlessness.

Medical researchers examining data on oxygen support technologies
Preclinical and early human studies are focused on safety, feasibility, and how much extra oxygen intestinal delivery can realistically provide.

Risks, Unknowns, and Ethical Questions

Turning the intestine into an emergency gas-exchange surface is a radical idea, and scientists are approaching it cautiously. Some key concerns include:

  • Infection risk: The gut is full of bacteria. Introducing devices or fluids could:
    • Increase the chance of bloodstream infections (sepsis) if not perfectly sterile.
    • Disrupt the gut microbiome.
  • Inflammation and injury: The intestinal lining is delicate.
    • Too much pressure, incorrect fluid composition, or improper technique could cause tearing or inflammation.
    • Animal studies that used abrasive methods are not acceptable in humans, so safer human-specific protocols must be developed.
  • Limited oxygen capacity: Even in best-case scenarios, the gut will likely never match the lungs’ oxygen-delivery power. This makes it a partial boost, not a full replacement.
  • Consent and dignity: The rectal route is intimate and may feel embarrassing for patients or families to discuss, especially in cultures where it’s taboo.
  • Fair access: If this technology proves effective, how will it be shared with low-resource hospitals that might benefit most from a lower-tech backup to ECMO?
“Just because something is technically possible doesn’t mean it should become standard practice overnight. We need careful trials, transparent communication, and ethical safeguards before intestinal oxygen delivery could be considered for real-world emergencies.”
— Critical care ethicist, summarizing current expert sentiment

Who Might One Day Benefit from This Technology?

If ongoing research continues to show safety and benefit, potential future uses could include:

  • Patients with severe ARDS or pneumonia whose lungs are so damaged that even high-level ventilator strategies are failing.
  • Overwhelmed ICUs where ECMO machines are already in use for other patients, and an extra “oxygen trickle” could buy time.
  • Low- and middle-income hospitals where ECMO is simply not available and an easier-to-implement backup could reduce deaths from respiratory failure.
  • Disaster or battlefield medicine where portable oxygen-delivery systems via the gut might help stabilize people until they reach a fully equipped facility.

Importantly, this would almost always be combined with:

  • Ventilation (helping the lungs as much as possible).
  • Circulatory support.
  • Urgent treatment of the underlying cause (infection, trauma, toxins, etc.).
Busy intensive care unit with healthcare team caring for ventilated patients
In resource-limited or overwhelmed ICUs, even a modest backup oxygen technique could potentially keep critically ill patients alive a bit longer.

Common Misconceptions About “Butt Breathing”

Because the idea is eye-catching, it’s easy for headlines to run ahead of the science. Let’s clear up a few misunderstandings:

  • “Humans can now breathe through their butts like turtles.”
    Not really. In research, intestinal oxygen delivery provides some extra oxygen under extreme, controlled conditions. It’s not a full substitute for normal breathing.
  • “This will soon replace ventilators or ECMO.”
    There’s no evidence for that. At best, it might become a bridge or backup in very select cases.
  • “It will be a cure for COPD or chronic lung disease.”
    Chronic conditions are complex, and long-term intestinal oxygen therapy raises huge safety and practicality issues. Current work is focused on short-term, emergency use only.
  • “You can do it at home with oxygen or special liquids.”
    Absolutely not. Attempting anything like this outside a clinical trial would be extremely dangerous and could be life-threatening.

What This Means for You Right Now

If you live with lung disease or worry about breathing emergencies, news like this can stir up both hope and anxiety. It might help to keep a few grounded points in mind:

  • Your best protection today is still the basics:
    • Vaccinations for respiratory infections when recommended (e.g., flu, COVID-19, pneumococcal).
    • Not smoking and avoiding secondhand smoke or vaping.
    • Managing conditions like asthma or COPD with guideline-based care.
    • Early medical attention if you’re struggling to breathe.
  • Intestinal oxygen delivery remains experimental. It’s not an option you can request at a typical hospital today.
  • For families of critically ill patients, it’s okay to ask ICU teams what experimental or advanced options exist, but expect that many will still be limited to clinical trials under strict rules.

One ICU physician I spoke with described a case where a young patient’s lungs were destroyed by sudden ARDS. The team used every available tool—ventilation, proning, ECMO—to keep him alive. “If we’d had a safe way to add even a small amount of extra oxygen, we would have tried it,” the doctor reflected. “Techniques like intestinal oxygen delivery might someday give us that little bit more.”


The Future of Emergency Oxygen: From Sci-Fi to ICU?

Looking ahead, researchers are working on several key steps before this can move from lab bench to bedside:

  1. Refining oxygen-carrying liquids to maximize oxygen content while minimizing irritation or toxicity.
  2. Designing specialized catheters that are comfortable, secure, and minimize infection risk.
  3. Conducting larger human trials to:
    • Measure exactly how much extra oxygen can be delivered.
    • Track side effects and long-term outcomes.
    • Identify which patient groups benefit most.
  4. Developing clear ethical frameworks for using such an intimate intervention in emergency, often non-consensual situations.
  5. Ensuring global access by exploring low-cost versions that don’t rely on extremely expensive equipment.
Doctor and researcher discussing future medical technology in a hospital corridor
Translating intestinal oxygen delivery from concept to clinic will require careful research, ethical oversight, and realistic expectations.

Key Takeaways and How to Stay Informed

To wrap up, here’s what’s most important to remember about the emerging science of “butt breathing”:

  • Researchers are exploring the intestine as an emergency backup route for oxygen delivery when lungs fail completely.
  • Animal studies and early human safety trials suggest this is biologically plausible, but it’s still highly experimental.
  • Potential benefits include buying time in severe respiratory failure, especially where high-tech equipment is scarce.
  • Risks and unknowns—like infection, gut injury, limited oxygen capacity, and ethical concerns—mean that widespread clinical use is still years away, if it happens at all.
  • For now, the best way to protect yourself is to prevent severe lung illness and seek rapid care if breathing worsens.

If you’d like to follow this field as it evolves:

  1. Look for updates in reputable medical journals and news outlets that link to peer-reviewed research.
  2. Ask your healthcare team about advances in respiratory failure treatment that might apply to your situation.
  3. Be wary of products or clinics that promise “revolutionary oxygen therapies” without solid evidence.

Medical innovation often starts with ideas that sound bizarre at first. Gut-based oxygen delivery is one of those ideas—provocative, imperfect, and still unproven. But under the right safeguards, it might someday give doctors a life-saving option when all others have run out.

Your call to action: Keep your lungs as healthy as you can today, stay curious but skeptical about new treatments, and remember that behind every bold headline there’s a careful, step-by-step scientific process working to turn possibilities into safe realities.

Person taking a deep breath of fresh air outdoors symbolizing healthy lungs
While scientists explore radical backups for failing lungs, everyday lung health—fresh air, prevention, and good medical care—remains your most powerful tool.