Category: Actions



Introduction and description

Illustrations by Barbara Tagenaga

Carbogen, also called Meduna's Mixture after its inventor Ladislas J. Meduna is a mixture of carbon dioxide and oxygen gas.

Meduna administered carbogen to his patients "to help them relive traumatic experiences in order to purge them of their emotional excesses" ; a type of catharsis. It also "helped his patients become conscious of repressed traumatic events".  With proper preparation and administration, he found could "help clients become free of their neuroses".

Carbogen has also been used in psychology and psychotherapy to determine how a patient would react to an altered state of consciousness or to a sensation of loss of control. Individuals who reacted especially negatively to carbogen were generally not administered other drugs for fear of similar reactions.

The use of air with a high carbon dioxide content is much older than Meduna however.  Underground CO2/Sulphur dioxide etc gases from volcanic vents have long been used for divination and it is this connection that often made a site ‘holy’ or ‘sacred’  in the past, for example at Delphi.

Meduna's original formula was 30% CO2 and 70% oxygen.  Nowadays carbogen can refer to any mixture of these two gases, from 1.5% to 50% CO2,   - which makes it rather a risky thing to try.


Although I have described this 'medicine' used by the psychologists as a manufactured product, it is worth  bearing in mind that one can accidentally breathe Carbogen produced from a number of both natural and other processes. 

Carbon dioxide is emitted naturally from volcanoes, hot springs, and geysers; and freed from carbonate rocks by dissolution. 

Commercially carbon dioxide can come directly from natural carbon dioxide springs, where it is produced by the action of acidified water on limestone or dolomite.   There are also a number of known chemical routes to carbon dioxide. For example:

  • the reaction between hydrochloric acid and calcium carbonate (limestone or chalk) is: 2HCl + CaCO3 → CaCl2 + H2CO3 .  The carbonic acid (H2CO3) then decomposes to water and CO2. Such reactions are accompanied by foaming or bubbling, or both.
  • The combustion of all carbon containing fuels, such as methane (natural gas), petroleum distillates (gasoline, diesel, kerosene, propane), but also of coal and wood, will yield carbon dioxide and, in most cases, water. But of course it can also produce other gases which are toxic.  You have to know your chemical formulas.  As an example the chemical reaction between methane and oxygen is  CH4 + 2 O2 → CO2 + 2 H2O
  • Leavening agents produce carbon dioxide to cause dough to rise. Baker's yeast produces carbon dioxide by fermentation of sugars within the dough
  • Chemical leaveners such as baking powder and baking soda release carbon dioxide when heated or if exposed to acids
  • Yeast metabolizes sugar to produce carbon dioxide and ethanol, also known as alcohol

Carbon dioxide  is used in many consumer products that require pressurized gas because it is inexpensive and nonflammable and because it undergoes a phase transition from gas to liquid at room temperature at an attainable pressure of approximately 60 bar (870 psi, 59 atm), allowing far more carbon dioxide to fit in a given container than otherwise would.

  • Life jackets often contain canisters of pressured carbon dioxide for quick inflation
  • Aluminium capsules of CO2 are also sold as supplies of compressed gas for airguns, paintball markers, inflating bicycle tires, and for making carbonated water.

So there are other routes to being dosed on carbogen besides your local psychologist.


If you are lucky you will simply get hallucinations or perception recall, but as it is all too easy to overdose - either deliberately or accidentally-  then one should expect the following, all signs of having been poisoned

  • flushed skin
  • raised blood pressure followed by hypotension  - together with irregular Heart Rhythm and Tachycardia
  • dry mouth, dilated pupils
  • a feeling of anxiety and wish to run or flee, at worst total panic
  • tightness in the stomach, and intestines
  • muscle twitches, hand flaps
  • involuntary hyperventilation
  • convulsions
  • disorientation followed by unconsciousness

 All these are signs for your psychologist to get you out quick and help you to breathe normally.  If he or she doesn’t you could die.  After the event you may find the overall negative effects might be

  • Short term Memory loss
  • Nausea and Vomiting
  • Hyperventilation - to restore oxygen supply
  • Shock  - you may go very cold
  • Headache

The long term risks if you do not take the advice and use this frequently are described as

"Brain cell death  - leading to permanent loss of neurological function ranging from difficulty in concentration or loss of short term memory capacity through severe, lifelong mental disability".

How it works

Technically the name given to what we induce is Hypercapnia or hypercapnea.  It is a condition where there is too much carbon dioxide (CO2) in the blood. Hypercapnia normally triggers a reflex which increases breathing and access to oxygen, but of course if we continue to breathe in the carbogen it does not increase the amount of oxygen.

When carbogen is inhaled, the increase of carbon dioxide in the lungs causes a perception in the brain, both psychological and physiological, of suffocation because the brain perceives an increase in carbon dioxide levels in the lungs as a decrease in oxygen levels. ... Therefore, inhalation of carbogen causes the body to react as if it were not receiving sufficient oxygen.

Asphyxiation .

During asphyxiation we are essentially dying and  because we are ‘dying’  - dying for those who have not cottoned on to this, is regarded by the body as a threat [sorry cynicism crept in here]  - the body reverts to only essential functions and much of our  reasoning and memory are not essential functions.  Thus these two functions are actually suppressed

What takes the place of these functions is an overwhelming input of messages from the sensory systems – all of them – that says HELP HELP HELP – we are being deprived of oxygen – all of us, we are dying DO SOMETHING. 

But the Will, is unable to do something – it has no learnt function with which to counter the Threat and it is struggling all the time to ensure the Autonomic systems keep going.

Eventually the Will exhausted by the battle, gives in and the Composer takes over and we have our spiritual experience

References and further reading

 EROWID's section on carbogen

Carbon Dioxide Therapy - Meduna, Ladislas J. (1950).. 

Modified oxygen mask to induce target levels of hyperoxia and hypercarbia during radiotherapy: a more effective alternative to carbogen.  - Prisman E, Slessarev M, Azami T, Nayot D, Milosevic M, and Fisher J. (2007). International Journal of Radiation Biology. Jul;83(7):457-62.


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