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Drug info - Carbogen

Discussion in 'Various drugs not covered by other forums' started by Pharmacon23, Aug 24, 2006.

  1. Pharmacon23

    Pharmacon23 Newbie

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    Aug 24, 2006
    I have read some things about a mix of gasses called Carbogen or Meduna's Mixture, which is 70% Oxygen and 30% CO2.

    It was used in the past in psychotherapy to see the way pacients react to strong psychedelic experiences and is said to have effects similar to strong psychedelics like LSD and mescaline.

    Theoretically, carbogen works the follwong way:
    When the body detects large amounts of CO2 in the lungs, it is usually a sign that the individual is choking or drowning, etc. Logically, if CO2 levels rise dramatically, O2 levels fall to a life-threatening level. So if the body detects large amounts of CO2 in the lungs, it will trigger panic reactions because it thinks there is no more oxygen. This way, the individual feels like dying, even if there is enough oxygen to keep him alive. This leads, theoretically, to NDEs (Near-Death Experiences), which are described to be like a very strong hallucinogenic trip.

    I never tried this, because I'm kinda afraid to do this. If anyone has experiences or more info on this, pls post.
  2. Thirdedge

    Thirdedge Gold Member

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    Oct 25, 2005
    from earth
    This is interesting but said to cause an extremely unplesant reaction in many people. Used in psychedelic therapy in the 60,s to test a patients suitably to partake in psychedelic therapy.
  3. Paracelsus

    Paracelsus Platinum Member & Advisor

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    Aug 31, 2006
    from U.S.A.
    Yeah, I read something about this, too. Well, actually, its true that it causes very unpleasant experiences in some pacients, but thatz why it was used. To see how pacients react to psychedelics.

    I will definitely try this out, since its soooooooo easy to make (take CO2 from chargers which convert water into H2CO3 (an intelligent word for fizzy water :))) and you can get O2 by electrolyzing water.

    I'll be back soon with the report of my experience(s).
  4. donkey rhubarb

    donkey rhubarb Newbie

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    Feb 16, 2007
    Re: Any experiences with carbogen??

    SWIM wonders if SWIPar ever went ahead with this experiment. I am very interested as he finds the particular substance fascinating.

    I have also wondered if carbogen may be what Frank is inhailing in Blue Velvet...

    I remember Myron Stolaroff talking about carbogen making him use profanity which is somewhat similar to what happens to Frank..
    Last edited: Apr 23, 2007
  5. Paracelsus

    Paracelsus Platinum Member & Advisor

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    Aug 31, 2006
    from U.S.A.
    Re: Any experiences with carbogen??

    Sorry, I didn't go ahead in this, because he checked and the amounts of O2 obtained from electrolyzing water are just too small. As soon as I will come around some O2 of acceptable purity, he will conduct this experiment.

    SWIM doubts carbogen is enjoyable, but he will probably survive it. (everything that doesn't kill you makes you stronger :D)
  6. Veteran Joker

    Veteran Joker Newbie

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    Apr 14, 2007
    Re: Any experiences with carbogen??

    Breathing exercises in yoga and meditation offer a similar experience to this. Near death experiences stimulate the pineal gland, one of the substances being produced is DMT, information of which is available here and on the erowid vaults.

    A word of caution: Do not inhale highly oxygenated mixtures for extended periods of time as this may cause blindness (renal faliure) and pure oxygen is dangerous to inhale. Keep all naked flames and embers away from pure oxygen as it will cause the fires to be amplified greatly.
  7. Shampoo

    Shampoo entity of sorts Staff Member

    Reputation Points:
    Nov 10, 2007
    from france
    Re: Any experiences with carbogen??

    Though many forms of meditation are based on regulation of oxygen consumption and blood flow, the vastly increased level of carbon-dioxide intake is rarely intentionally mimicked.

    Carbogen delivers a specific blend of the two essential gasses to regulate both oxygen consumption, and at endogenous reactions to intensified co2 levels. Commonly, the result manifests as a sense of suffocation or drowning, and when controlled, can be useful in evoking specific endogenous chemicals.

    Inspired initially by Huxley's brief experimentation with the substaqnce, I has had 2 experiences with Carbogen, with varying co2 percentages (the first 20/80 o2/co2, the second 30/70 respectively). Both experiences were invariably lackluster, though the higher co2 content induced a relatively controlled panic state (mildly terrifying, though not entirely undesirable). swim found that the most enjoyable portion of Carbogen intoxication was the euphoria and physical sedation that manifested as a result of released tension after the inhalation had ceased. He found it similar to a common sense of relief after extended worry.

    for the record,
    This is a highly debated speculation without empirical evidence, based primarily on assumptions about the pineal gland and it's functions populated by Dr. Strassman's "DMT: The Spirit Molecule".

    See: https://drugs-forum.com/threads/34730&highlight=Pineal+Gland for discussion.
  8. Paracelsus

    Paracelsus Platinum Member & Advisor

    Reputation Points:
    Aug 31, 2006
    from U.S.A.
    Carbogen Introduction & Experiences (Erowid)

    Carbogen: An Introduction

    by B. James & Earth Erowid
    June 2007

    What is Carbogen?

    "Carbogen" refers to a gaseous mixture of carbon dioxide (CO2) and oxygen (O2), most often administered via a mask attached to a regulator connected to a high-pressure cylinder. The ratio of 30% CO2 and 70% O2 is known as "Meduna's mixture", after Ladislas J. Meduna, a psychiatrist who pioneered its use as a therapeutic tool in the 1940s and 1950s. Although carbogen—sometimes described in the medical literature as a "panicogen"—is perhaps best known for inducing anxiety, sensations of suffocation, and unconsciousness, this extremely simple gas can cause surprisingly complex psychoactive effects when inhaled for even a few breaths. Reports of discomfort and anxiety experienced while breathing carbogen may be partially explained by the set and setting of traditional carbogen administration rather than properties inherent in the substance itscarbelf. Recent reports of positive, or even glowing experiences suggest carbogen may be more properly described as a unique psychedelic.

    Although carbogen has been used safely for over 50 years, prolonged exposure to high levels of carbon dioxide can be fatal. Individuals with weakened respiratory health or any pulmonary disease are at much higher risk of potentially life-threatening responses. Additionally, those suffering from panic or psychotic disorders are more likely to experience adverse reactions (see Carbogen in Psychiatric Research below).

    The Experience

    Carbogen doses are typically measured in number of breaths, with a fully immersive experience resulting from 8–20 breaths. The maximum number of breaths administered, even in extreme cases, seems to be 30–50. Inhaling more than 50 breaths of Meduna's mixture is generally considered unproductive and increasingly dangerous.

    Most people remain relatively still for the duration of the experience. As few as 1–5 breaths can cause significant alterations of thought, perception, and mood; rushes of sensation in the body; and disorientation. During these first moments it may require a willful effort to continue inhaling the acidic-tasting gas. After a few more breaths, effects increase in intensity, and awareness of the external world fades away. People often close their eyes and those who keep them open exhibit an unseeing stare. Breath rate generally increases and breathing becomes somewhat labored.

    When inhaled at sufficient doses, carbogen has anaesthetic and dissociative effects, frequently accompanied by both open- and closed-eye visuals. These effects include brightening or darkening of the visual field, kaleidoscopic or swirling changes in color, and geometric patterning.

    Some people experience visions of more complex dreamscapes involving recognizable people and objects, or the sensation of being transported to another place or being in another dimension. Reports may include spiritual elements such as ineffable, numinous mental states, or encountering angelic beings.

    Psychoactive effects continue to develop for a short period after the final breath. They then subside rapidly with subjects returning to near baseline within 45–180 seconds after the last inhalation. As the effects fade, the feeling of having experienced more than can be remembered is common. In another parallel with more traditional psychedelics, Meduna noted that a small number of his subjects vividly re-experienced insights or memories that surfaced in carbogen sessions hours later or even the following day.1

    Although the cognitive component of the experience varies substantially from person to person and from experience to experience (as with many psychedelics), perhaps the most universally accurate descriptor is simply "intense".

    Physical Effects

    Physical symptoms frequently include rapid, deep, or shallow breathing. Even though carbogen contains more oxygen than ambient air, its higher-than-normal levels of carbon dioxide trigger brain reflexes associated with asphyxiation (see Carbogen Pharmacology below).

    Meduna reported other physical symptoms, such as eyelid fluttering and body spasms, but more recent carbogen reports do not support these as universal or even particularly common. At 10–30 breaths, some subjects flex their leg and hip muscles, or have carpal spasms (involuntary finger and wrist curling) similar to those sometimes experienced during Holotropic Breathwork. In intense sessions (40 breaths or more), Meduna reported that some subjects underwent convulsions, seizures, or bicycling of the limbs.

    Anxiety and Discomfort

    When inhaling carbogen, it is common for subjects to feel that they are not getting enough oxygen. A recent experimenter said, "It's like feeling like suffocating".2 One of Meduna's patients reported: "In every case, when inhaling the gaseous mixture I experienced a terrifying smothering sensation; and before the moment of narcosis I had to exert every bit of my will power to keep from fighting the mask."1

    These feelings of suffocation can cause mild to severe anxiety, fear, or panic, as described by another patient: "After three or four inhalations, the feeling of suffocation becomes intense. And then it becomes necessary to breathe fast. About this time I start praying, 'Oh, God, please help me to go under this quick,' and it usually helps. However, there are times when nothing helps, I am so filled with panic."1

    In a similar spirit, Dale Pendell captures the flavor of a very unpleasant experience: "It's bad from the first lungful. It tastes sour. Alarm bells go off immediately. 'This is bad.' Will power is required to take even one full inhalation. By the second lungful, if you haven't ripped the mask off, full panic has set in. You need AIR! People start gasping at this point, faces flushed and sucking in the carbogen furiously."3

    This feeling has also been described as generalized anxiety: "I got 'that scary feeling', the early tinges of the fear that I might get as I approach the difficult part of a [psychedelic] trip."4

    Psychiatric research using carbogen has found that those who have anxiety or panic disorders are more prone to negative reactions than the general population. Some research has also shown that a majority of subjects experience at least some symptoms of increased anxiety during extended "carbon dioxide challenges".5 Meduna found that administering carbogen in shorter sessions (no more than 30 breaths) seemed to help. He observed that fear often grew more intense as a session progressed.

    Descriptions of carbogen's unpleasantness abound. A 1992 book by Trevor Trueheart briefly mentions carbogen: "Everybody I have known to inhale carbogen experienced extreme fear and seemed to confront all the demons stored in his or her unconscious. This is the stuff of nightmares".6

    Euphoria, Pleasure, and Visions

    In stark contrast to the many negative reactions are the extremely positive, sensual, or euphoric responses. In fact, Yacorzynski, et al. (1962) reported that more of their subjects "enjoyed" the experience than found it frightening. Recent work by B. James (see Carbogen Redux) involving subjects familiar with psychedelics confirmed that a majority of those who were administered carbogen in a friendly setting did not have fearful reactions, and many found the effects pleasurable. Giggling and laughing were common and "wow" was probably the most frequently uttered word after a person's first experience.

    Immediately following his first experience with carbogen (15 breaths), one person took 4 breaths of normal air and then exclaimed excitedly: "Yeah, this is fucking awesome. This is it, I love this. Fuck, this is so cool! [breathing hard, laughing] That's wonderful shit. Excuse my language. [breathing calms] It didn't feel alien to any experience I've had; it seems akin to the more euphoric states of nitrous."4

    Many people report enjoying the aesthetic effects or visions, as in these 1998 reports: "It was intensely beautiful."2 and "Oh my, it was neat. I went to this paradise land: wow! […] I went through a brightly starry zone, then drifted on past that to a lush, green paradise. It was neat: beauty. It was very good."2

    Some subjects immediately comment that they'd like to try it again: "I sure went someplace that I've never been before. Yeah, I think that I'd love to go back." Others comment on the experience with superlatives: "I like that stuff. It could be the best."2

    Positive psychedelic effects have also been reported by subjects administered carbogen in medical settings, such as this account from a session administered by Meduna1:

    Meduna commented that, "In this beautiful experience we can discern almost all the constants of the CO2 experience: (1) Color; (2) Geometric pattern; (3) Movement; (4) Doubleness of personality; and (5) Divination or feeling of esoteric importance."1

    Expectation and Mindset

    The disparity between panicky, uncomfortable experiences and pleasurable, spiritual ones raises questions about what accounts for these differences. The bias towards negative descriptions may be partially the result of the fact that Meduna administered carbogen primarily to individuals seeking treatment for emotional or mental problems. It may also result from the expectations of researchers and participants.

    Yacorzynski, et al. (1962) found that the majority of their subjects did not experience feelings of fear, speculating that was due to differences in the briefings given beforehand.7 After administering carbogen to dozens of participants, B. James came to believe that the quality and type of experience may be as strongly affected by methods, contexts, and expectations as they are with most psychedelics. Set and setting may be critical factors in the experience of carbogen. Psychiatric research into anxiety using carbogen confirms this, with a number of papers showing that a sense of safety, feeling in control of the administration of the gas, an understanding of carbogen's effects, and having a "professional" present during the session can all lead to reduced anxiety.8

    Although the literature is dominated by descriptions of anxiety and discomfort, it may actually be that most people who breathe carbogen in an appropriate setting do not experience strong unpleasant effects.

    Carbogen's History in Medicine

    Inhaled carbon dioxide has been known to have psychoactive effects since at least 1827, when Henry Hickman demonstrated that a dog exposed to an atmosphere containing carbon dioxide became anaesthetized. In 1856, the author Sir James Simpson stated that, "Carbon dioxide is recognized by toxicologists as a very powerful narcotic poison when inhaled in sufficient quantity."1 Carbon dioxide was explored as a medical and psychiatric tool in the late nineteenth and early twentieth centuries.

    The golden age of carbogen research in psychiatry arrived in the 1940s and 1950s, spearheaded by the work of Ladislas Meduna. Born in 1896, Meduna was a Hungarian psychiatrist who emigrated to Chicago in 1938. He developed a deep interest in psychiatric therapies involving sleep, coma, and related non-ordinary states of consciousness and was an early pioneer in chemical and electroconvulsive therapies.

    Meduna began researching carbogen therapy in 1943 and over the course of his career conducted more than 15,000 carbogen "treatments".1 His standard procedure consisted of administering between 10 and 50 inhalations of the 30% CO2 / 70% O2 mixture in short sessions, three times per week.

    Meduna reported success in using carbogen to treat several "psychoneurotic conditions" including stuttering, anxiety, spastic colitis, frigidity, and homosexuality. He reported that carbogen frequently induced the surfacing of repressed emotional responses, which he considered unrelated to carbogen's therapeutic effects. Meduna discussed the possibility that the intensity of the experience, coupled with the brief unconsciousness it induced, might help desensitize patients to anxiety or fear, but largely considered carbogen's benefits to be a result of direct physiological action on the brain.1

    In 1950 Meduna published the first edition of the definitive monograph on carbogen in psychiatry, Carbon Dioxide Therapy. In the 1950s carbon dioxide therapy research expanded and was used by other psychiatrists in conjunction with electroconvulsive therapy (also known as "electroshock therapy"). It was also co-administered with psychoactive drugs such as atropine, barbiturates, and antihistamines, although Meduna argued that combining carbogen with depressants could be dangerous.

    While Meduna reported successes with carbogen, other researchers ultimately recommended against its use as an adjunct to psychotherapy. For example, Hargrove, et al. reported in 1954 that, "The use of carbon dioxide therapy in our hands added no specific therapeutic effect but did add problems of transference and resistance that retarded or prevented recovery."9

    Carbogen use was investigated in the mid-twentieth century for a remarkable breadth of maladies ranging from depression, neuroses, psychoses, and dementias, to rheumatoid arthritis, cerebral palsy, Parkinson's disease, asthma, pneumonia, hiccups, and whooping cough.7,10,11 In recent years, several studies have indicated that carbogen may help make certain cancerous tumor cells more susceptible to radio- and chemotherapies.12 Carbon dioxide also continues to be used in medicine for its ability to stimulate breathing and cause vasodilation.

    Carbogen in Psychiatric Research

    Interest in carbogen as a psychotherapeutic tool waned in the 1960s. It was then increasingly investigated—in "carbon dioxide challenges"—for its capacity to cause anxiety and panic rather than treat them. In contemporary psychiatric research, carbogen has been "extensively used" in this type of study at concentrations of 5–35% carbon dioxide.13 It is notable, however, that recent research does not use the strong doses administered by Meduna, instead delivering high concentrations for only brief periods. As Zvolensky, et al. describe in a 2001 review of this field of research: "5% CO2 typically is administered steadily for 15 min, 20% CO2 for 20–25 [sec], and 35% CO2 in a single vital capacity breath."8

    One typical research protocol, published in 2001, administered 5% CO2 for twenty minutes to subjects lying in a "respiratory canopy" and rated them for symptoms of panic. They found that 52.0% of those who had previously been diagnosed with panic disorder had a panic reaction, while 8.8% of the "normal comparison subjects" exhibited symptoms of panic.5 Other researchers have found an even wider disparity.

    Carbogen's capacity to trigger anxiety has been used to evaluate treatments for anxiety disorders as well as the etiology (source) of panic reactions. In one double-blind study, panic responses triggered by carbogen were dramatically reduced in subjects with panic disorder by pre-treatment with 1 mg alprazolam (Xanax).5 Several carbogen studies have also shown that the closer one's familial relationship to a panic disorder sufferer, the more likely one is to experience panic during a carbon dioxide challenge.14

    Carbogen and Psychedelics

    Alfred "Al" Hubbard, an important early advocate of psychedelics, appears to have been one of the first major proponents of carbogen within the psychedelic subculture. Hubbard traveled the world introducing famous and influential people to LSD and carbogen. As Jay Stevens describes in Storming Heaven, "One of Al's favorite break-the-ice devices was carbogen, a mixture of carbon dioxide and oxygen, which came in a small portable cylinder. Carbogen was what therapists referred to as a potent abreactor: ten or fifteen lungfuls and you tended to relive your childhood traumas. And judging on how well you handled them, Al would either offer to run an LSD session for you, or he wouldn't."15 Carbogen was, literally, Hubbard's (pre-) acid test.

    Aldous Huxley, who received his first dose of LSD from Hubbard, recounts in Heaven and Hell16:

    Huxley and others speculated that spiritual practices involving the breath such as chanting or yogic breathing may induce religious visions through altering CO2 concentrations in the blood.16 Stanislav Grof, a well-known researcher into LSD's psychotherapeutic effects, and Christina Grof later developed Holotropic Breathwork, a method of hyperventilation designed to legally mimic some of the beneficial effects of LSD. Holotropic Breathwork also produces its effects by directly manipulating CO2 levels, though by decreasing rather than increasing CO2 concentration in the blood.

    Hubbard claimed to have conducted 1,700 LSD sessions by 1959, and his reputation piqued the interest of Myron Stolaroff, who went on to become an important figure in research into non-ordinary states of consciousness. Stolaroff writes, "Hubbard made a deeper impression on me than anyone I had ever met. It was an impression that radically altered my whole value-belief system, and completely changed the course of my life."17 The first day they met, Hubbard gave Stolaroff a tablet of methedrine and a few inhalations of Meduna's mixture. "No doubt reading me quite accurately," Stolaroff recalls, "he gave me only a few breaths, but it was enough to give me a glimpse, and especially a feeling, of another world."17 Stolaroff was profoundly impressed, and they arranged an LSD session.

    Stolaroff's LSD session was life-changing. Convinced of its therapeutic potential, he set up the International Foundation for Advanced Study in Menlo Park, California in 1961. Stolaroff continued to work with carbogen: "In our Foundation work with clients, we found that several treatments with [Meduna's] mixture was an excellent procedure to introduce novices to altered states of consciousness. Many discovered unconscious contents of their mind for the first time. The procedure also cleared away a good deal of repressed material, thus freeing the subject for a smoother, more profound psychedelic experience." Although he considered carbogen beneficial, he noted "[…] it was such a drastic and dramatic procedure that no one underwent it eagerly."17

    As a counterpoint, however, Stolaroff also describes a person who had a positive reaction to carbogen as "a complete standout. […] Jeffrey was quite an exception. He loved it. He would take an enormous number of breaths—up to 50".17 Such positive experiences were considered distant outliers. As legal psychedelic research became less common, interest in this potentially dysphoric psychoactive outside of research contexts was minimal, and carbogen experimentation largely disappeared.

    Carbogen Pharmacology

    The mechanisms of action for carbogen's psychoactive effects have not been fully established. During the 1950s and 1960s, the primary mechanisms proposed were alterations in blood pH and inhibition of neuronal function by the slowing of cellular metabolism. More recent research paints a complex picture of interconnected systems, including activation of serotonin (5-HT) neurons in the raphe nuclei (located in the mid-brain) where most serotonin neurons have their cell bodies.18,19,20

    The air we breathe normally contains 20–21% oxygen and 0.02–0.06% carbon dioxide, with nitrogen and trace gases constituting the other 78.9+%. Meduna's mixture is 30% CO2 and 70% O2, giving it much higher concentrations of both than normal air. Although some people have reported mildly calming psychoactive effects from breathing pure oxygen, it is the extremely high levels of carbon dioxide (around 1000 times normal levels) to which carbogen's effects are attributed.

    Counterintuitively, the physiological urge to breathe is mostly a response to high levels of CO2 rather than to low levels of oxygen in the blood. While the body has some oxygen-based triggers, these account for only a small portion of the impulse to breathe. The carbon dioxide–driven breathing reflex explains why taking a lungful of 100% helium or nitrous oxide does not immediately cause the sensation of suffocation. In humans, central and peripheral chemoreceptors (chemical "sensors" inside and outside the brain) constantly monitor carbon dioxide levels in the blood to determine how strongly to breathe. Cells produce carbon dioxide as they use energy. When a person holds his or her breath, carbon dioxide levels rise in the blood and the chemoreceptors send "breathe more" alerts to the body and brain with increasing urgency. Carbogen triggers this response even though oxygen levels in the lungs and blood are higher than normal.21 Simply holding one's breath does not cause carbogen-like effects.

    Carbon dioxide dissolved in blood is acidic, just as it is in carbonated soda. Inhalation of carbogen rapidly increases acidity (lowers pH) of the blood, cerebrospinal fluid, and brain, creating a condition called respiratory acidosis or hypercapnia. In 1938 Gibbs and Gibbs repeatedly measured arterial and venous blood pH while administering a 35-breath session with Meduna's mixture. They found that arterial blood pH dropped from 7.37 at the start of the session to 6.94 after 35 inhalations17, a level that could be dangerous if maintained for prolonged periods. Blood pH rapidly returns to normal after carbogen administration ends. Although many researchers believe that lowered pH directly causes reduced brain activity and anaesthesia22,23, acidosis alone probably does not explain carbogen's visual and visionary effects.

    Interestingly, high levels of carbon dioxide also lead to rapid dilatation of cerebral vessels and increased cerebral blood flow.23,24 For brief periods, increases in blood flow in the brain are generally associated with improvements in cognitive performance.

    Recent advances in understanding the identity and location of the brain's carbon dioxide chemoreceptors may provide better explanations for the anxiogenic and visionary effects of carbogen. Over the last decade, a number of researchers have verified that a subset of serotonin neurons in the raphe nuclei respond to hypercapnia.18 Because of the many brain areas to which they extend, such serotonin neurons are well-placed to not only trigger autonomic responses, such as breath and cerebral blood flow, but also interact with the parts of the brain responsible for cognition and emotions.19 Severson, et al. proposed in 2003, "that a major role of serotonergic neurons throughout the brainstem is to monitor the acid/base status of blood and to initiate multiple responses aimed at restoring pH to normal, including changes in behavior, breathing, and autonomic control."19 The highly-networked serotonin neurons—better known for their involvement with psychedelics, antidepressants, and higher brain function—are also valuable as CO2 detectors because of their wide connection to many brain systems. When high CO2 levels are detected, one might not only need to change breathing or increase heart rate, but may also need to be able to make complex, life-preserving decisions about how to get to a safer location.18,19,25

    Ongoing research into the neurophysiology of anxiety and panic disorder has revealed that carbogen-activated chemoreceptor neurons may directly affect many parts of the brain, triggering several receptor systems, including the adrenergic, cholinergic, and dopaminergic systems. Kaye, et al. (2004) summarize the results of recent brain imaging research showing hypercapnia's widespread effects: "humans exposed to CO2 have shown activation of numerous centres, including medullary, limbic and paralimbic (amygdala ad peri-amygdala), cerebellar, insula and prefrontal cortical areas."26,27

    Carbogen psychopharmacology is still quite speculative and continues to be actively explored. Although there are thousands of papers listed in PubMed looking at the physiological and mental effects of increased carbon dioxide in the blood, including hundreds from the last few years, as far as we know, as of May 2007, the mechanisms of carbogen's psychedelic-like effects have not been examined in the scientific literature since the 1950s.

    Carbon Dioxide Safety Questions

    Carbogen mixtures have been safely administered in medical and psychiatric procedures many thousands of times. While it appears to be relatively safe when administered in brief sessions, prolonged exposure to high levels of CO2 is sufficient to cause lethal respiratory or circulatory failure, as evidenced by the fact that CO2 is used to euthanize lab animals.28,29,30

    Hypercapnia is initially stimulating, but longer-term exposure to high levels of carbon dioxide leads to "carbon dioxide narcosis": lethargy, confusion, and sleepiness. Exposure to levels of carbon dioxide around 10% causes dizziness and higher levels cause unconsciousness within minutes.1 There have been a number of reported deaths where accidental exposure to high carbon dioxide levels caused the victims to black out before they could reach safety.28

    Complicating the safety picture is the fact that most real-world cases involve not only high levels of carbon dioxide, but hypoxia (low levels of oxygen) as well. Most information provided by governmental agencies about CO2 dangers is related to oxygen displacement. Serious accidents have been reported related to: dry ice (frozen CO2) sublimating into CO2 gas, beer brewing forming CO2, and malfunctioning ventilation systems increasing CO2 levels in submarines, among others. All of these involve hypoxia and are not exclusively attributable to CO2 poisoning.

    As Gill, et al. clarify in their 2002 article, it is important to distinguish between "simple asphyxiants" and "toxic gases". For example, nitrogen is a simple asphyxiant, meaning that if it displaces too much oxygen, it can cause suffocation, but as long as around 20% oxygen is maintained, it is safe to breathe indefinitely. Other gases, like carbon monoxide, hydrogen sulfide, or carbon dioxide can be fatal because of their chemical effects alone.28

    Research with animals has convincingly shown that adequate concentrations of oxygen do not prevent death from CO2 poisoning. One research protocol administered 80% CO2 and 20% O2 to dogs, causing death in 10–15 minutes. The same researchers also euthanized dogs with 50% CO2 and 50% O2, causing death in 30–90 minutes.29 Because of differences in metabolism as well as the long durations and high concentrations used, the animal research into CO2 poisoning is not easily translatable to human health concerns for short-term inhalation of carbogen.

    A primary danger of short-term inhalation of carbogen is accidental over-exposure, like the tragic but recurring unsupervised nitrous oxide suffocations caused by masks, garbage bags, or stuck tank valves. People with weakened respiratory systems, such as those with chronic obstructive pulmonary disease or cystic fibrosis, are at much higher risk of life-threatening complications from inhaling carbogen. Further, many heavy smokers have undiagnosed lung dysfunction that would severely weaken their ability to recover from acidosis caused by carbogen, putting them at much higher risk of respiratory failure than healthy individuals.31 Because carbogen inhalation causes a spike in cerebral blood flow, those with weak cardiovascular systems or health issues related to cranial blood pressure may be at higher risk of problems. Other populations may also be at higher risk, including schizophrenics or those suffering from anemia.

    Ubiquitous Entheogen?

    The psychoactive effects produced by a mixture of the common gases carbon dioxide and oxygen remind us that consciousness is a fragile knitwork of body, mind, and environment. Alexander Shulgin, the renowned psychedelic chemist, describes teaching a class in San Francisco after which a young man expressed interest in synthesizing LSD. Dr. Shulgin replied that LSD chemistry is very complex and that he should start off with something simple, like carbon dioxide. When the young man replied incredulously, Dr. Shulgin led him downstairs to a lab where tubs of dry ice were stored and suggested the student put his head down next to one of the tubs, inhale deeply through his mouth, and see how he felt. After taking two deep breaths and experiencing the psychoactive effects, he said, "Point taken".


    1. Meduna LJ. Carbon Dioxide Therapy. Charles C. Thomas. 1950. p 33,18,100,127,28,3,18,61,9,4–6.
    2. James B (ed.). Carbogen Logbook 1 (unpublished). 1998. s23,s37,s17,s41,s5.
    3. Pendell D. Pharmaco/Gnosis. Mercury House. 2006. p 271.
    4. James B (ed.). Carbogen Logbook 2 (unpublished). 2007. s4,s3.
    5. Kent JM, Papp LA, Martinez JM, et al. "Specificity of panic response to CO(2) inhalation in panic disorder". Am J Psychiat. Jan 2001;158(1):58–67.
    6. Trueheart T. Triplepoint: LSD in Group Therapy. 1992. p 11.
    7. Yacorzynski, Atkinson, Cohen, et al. Investigation of Carbon Dioxide Therapy. Charles C. Thomas. 1962. p 261,13.
    8. Zvolensky MJ, Eifert GH. "A review of psychological factors/processes affecting anxious responding during […] inhalations of carbon dioxide-enriched air". Clin Psychol Rev. 2001;21(3):375–400.
    9. Hargrove EA, Bennet AE, Steele M. "An investigation of carbon dioxide as an adjunct to psychotherapy in some neuroses". Am J Psychiatr. 1954 May;110(11):844–9.
    10. Campbell A, Poulton EP. Oxygen and Carbon Dioxide Therapy. Oxford Medical Publications. 1934. p 82,111.
    11. Hazardous Substances Data Bank: Carbon Dioxide. National Library of Medicine. Accessed May 2007.
    12. Minchinton AI, Tonn DA, Sutherland DP, et al. "Carbogen breathing after irradiation enhances the effectiveness of tirapazamine in SiHa tumors […] in mice". Radiat Res. 2002;158(1):94–100.
    13. Schmidt NB, Maner JK, Zvolensky MJ. "Reactivity to challenge with carbon dioxide as a prospective predictor of panic attacks". Psychiatry Res. 2007;151(1–2):173-6.
    14. Coryell W, Pine D, Fyer A, et al. "Anxiety responses to CO2 inhalation in subjects at high-risk for panic disorder". J Affect Disord. 2006;92(1):63–70.
    15. Stevens J. Storming Heaven. Atlantic Monthly Press. 1987. p 58.
    16. Huxley A. Heaven and Hell. Harper & Brothers. 1956. p 61–2.
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    Carbogen Redux: Contemporary Exploration of a Ubiquitous Inhalant

    by B. James
    June 2007

    Subjects and Materials

    In the last nine years, I have administered carbogen to over fifty people, aged 22 to 65 years old. Nearly all of them were well-accustomed to profound psychedelic states of consciousness, but none had previously experienced carbogen. Most participated in multiple sessions each consisting of 2 to 26 inhalations. I have used three different concentrations: Meduna's mixture (30% CO2 / 70% O2) and two slight variations: 28/72 and 34/66. The 34/66 mixture produced a faster onset of effect, with no other noticeable differences.

    All sessions involved pre-mixed gases in a single, high-pressure gas cylinder. For most sessions I used a pressure regulator and a mask with both a demand regulator and an extra exhaust valve. I added the extra exhaust valve to accommodate rapid exhalations (characteristic in carbogen subjects) that the standard valve couldn't handle. In a later setup I replaced the demand regulator with a bladder that was filled before the inhalations began. This allowed me to turn off the gas cylinder prior to carbogen administration, eliminating the risk of problems caused by open valves or a stuck demand regulator.

    Before administering carbogen to others, I considered it essential to experience it myself. I tried carbogen twice to gain the first-hand experience necessary for administering it to others.

    The Sessions

    In my role as sitter, I answered any questions I could, but tried to avoid unduly influencing people's expectations. I warned subjects that the carbon dioxide in the mix could trigger an intense feeling of suffocation, but that they would not be in danger because they would be breathing more oxygen than is in ambient air. Sometimes, I used an analogy of an "idiot light" in the brain that checks for CO2 concentration but ignores O2 concentration. I also told them that the gas could taste pretty bad, almost like drinking a Coke and burping through the nose.

    I asked each participant to select a maximum number of inhalations for their session, recommending between 10 and 25. I had participants lie down in a comfortable position and told them that I would count each breath out loud until I reached their chosen number. I told them I would then remove the mask, adding that if they made the slightest gesture during the session, I would immediately stop administering the gas. I mentioned that a new sensation could occur at around 7 or 8 breaths, replacing the initial discomfort, making it worthwhile to try to hold on through at least 10 inhalations. (One subject had a tremendously deep reaction to 2 breaths, so I agreed he could choose a low limit of 6 for his second attempt. At the sixth breath, when I removed the mask, he clutched at it, calling out "more, more . . . the angels!")

    I did not measure pulse or blood pressure during sessions, as physiological responses are well described in Meduna's Carbon Dioxide Therapy. My primary goal was to gather information about the subjective mental state of the experience, but I will briefly describe carbogen's physical effects. Subjects generally exhibited one of three breathing patterns:
    1. Deep and desperately rapid breathing starting by the second breath, and lasting into the teens. Somewhere before breath 20 the urgency tapers off and the subject settles into deep, rhythmic breaths.
    2. Deep, rapid breathing with a gagging pause, as if to swallow, every 3 or 4 breaths into the 20s.
    3. Calm, deep, slow breathing, through the 20s. One subject displayed this pattern during each session; another adopted it after his second session, and reported that it required quite a bit of will power.

    Involuntary eye movements often started in the teens and lasted for 10 to 30 seconds after the last inhalation. If a subject's eyes were open during the session, they were apparently not focusing on anything external. None of the subjects I worked with experienced anything that I would classify as an "abreaction" (release of repressed subconscious material) as described in the literature from the 1950s and 1960s. When I removed the mask after the final breath, people consistently breathed hard for up to a minute, as though they had just run a short sprint.

    After completing a session, many subjects attempted to put what they had experienced into words...
    • After 26 breaths, subject uttered in a profound tone, "Death is very personal." He later described that he had experienced every cell in his body dying. He said that after the seventeenth inhalation he "could have gone on and on in that state." It was "very peaceful, very serene, kind of like postcards from heaven."
    • Subject took 25 fast, deep breaths of carbogen with loud exhalations. His breathing quieted in about a minute and a half, and another minute later he exclaimed, surprised, "The mask's off? How many?" At his fourth inhalation he had seen "something coming on…colors." He and the other subjects in the room agreed, "It's essence-oriented".
    • Subject took 13 breaths and then said, "Oh my, it was neat. I went to this paradise land. Wow. [I was in a] brightly starry zone, I drifted past that to lush, green paradise. […] After about 4 breaths I saw the stars and didn't think much about the breathing discomfort. […] It was very, very visual once I got past the star land. Then I was coming back and it's like, wait a minute! […] Similar to but totally different from DMT, even as far as the feeling of being just yanked."
    • Subject took 24 inhalations and announced with a wide smile, "Oh, that was wonderful."
    • Subject chose to take 13 inhalations, but stopped at 6, saying, "I can't imagine pushing it beyond that. It was incredible! Bright light, brighter than nitrous, and very alive. Impressive color."
    • Subject found the entire experience uncomfortable, describing it as "dreadful". At 65 years old, this was the oldest subject. When asked to pick a number of inhalations, he blithely replied, "Why wouldn't I choose 25?". He emitted a low howl on every exhalation for about 30 seconds after the last breath. He described that it felt like he would suffocate and could not get over the discomfort. He said, "Glad I did it, but I'm not ready to do it again." He later explained that he had furiously resisted ether anesthesia as a child, and several doctors and nurses were required to hold him down before he went unconscious. Similarly, he fought his carbogen experience with all his will, in order to avoid giving up control.
    • Subject took 10 inhalations, then giggled, "That was great."
    • Subject took 25 breaths. During the experience, his body shook, seizure-like, then his left leg went up, then his right hand went into the air and he vocalized something unintelligible. After two minutes, his eyes changed to a look of recognition and his arm lowered and he said, "Wow, that was really intense! There was a whole blast of light and an interaction, that's why I had my hand up… a whole dream sequence like something out of Star Wars."
    • Subject took 15 breaths and later wrote, "It was very different from my expectations. I barely even noticed the taste of the gas. I wasn't aware of any feeling of not having enough oxygen. I felt a surprisingly gentle sensation of drifting into a deep place of contentment, like I was floating down under the water, and colors were rising up to receive me. I was floating in a place outside of gravity, outside of boundedness."

    Different Set & Settings

    As part of the protocol for the first U.S. group I worked with, I decided to direct potential subjects' questions about carbogen's effects to those who had already experienced it. I learned a great deal from listening to these accounts, and was surprised to hear sessions described in increasingly positive terms. The descriptions of ecstatic states were far beyond what I had expected.

    I later conducted sessions with a large number of participants in the Netherlands. The setting was a dedicated spiritual space among "seekers" who had gathered for a psychoactives-oriented conference taking place in Amsterdam. I truncated the verbal part of my protocol for this group, since the subjects generally did not speak much English. They were asked to pick a number of breaths, but there was little discussion about expectations and potential effects. In this group, no subject stopped before their selected number of breaths. As with the U.S. group, the predominant reaction was "wow". There was no indication that any of these subjects experienced negative effects.

    I hosted additional sessions in the United States, one with a small group of "drug geeks" curious about the effects of carbogen. They had researched and discussed carbogen with one another and had a sense of what they might expect. Individuals in this group were fairly conservative in the number of breaths they chose: between 5 and 22. Although I expected this group to choose higher numbers of inhalations, their collective opinion seemed to be that there was no clear benefit in going for more breaths; most thought that over 10 or 15 would not necessarily be more interesting or valuable.

    Sometimes I saw what appeared to be terror or deep concern on people's faces, only to have them describe their experiences as wonderfully positive or at least neutral. For example, one subject's eyes shot open immediately after the mask was removed in what looked to observers to be an expression of fright or astonishment, yet he related an extremely positive, numinous mental state.

    Closing Thoughts

    In early sessions, I felt it was best to fully disclose the potentially uncomfortable physical sensations often experienced in the first 10 breaths. After administering carbogen dozens of times, I found that most people did not have much trouble with the experience. Because of this, I felt it was less necessary to spend time describing possible negative reactions to later subjects. I wonder what the reactions would be if pre-session preparation focused on positive aspects of the carbogen experience.

    Clearly, the profound experiences generated by psychedelics can be highly influenced by suggestion. It seems this is true for carbogen as well. Although some early authors reported frequent negative reactions to carbogen, in my sample of more than 50 subjects, only one exhibited an obvious negative reaction and none appeared to abreact. This may be because my subjects' previous work with psychedelics left them clear of psychic debris. Or they may simply have been accustomed to powerful psychoactive effects, and thus better prepared for the experience. Also, all of the subjects to whom I administered carbogen were specifically interested in having a carbogen experience rather than receiving it as a part of therapy or research. Finally, when carbogen is presented as an extraordinarily powerful but intrinsically neutral or positive experience, it appears to be less likely to produce a negative reaction.
    Last edited by a moderator: May 20, 2011
  9. Archangelus

    Archangelus Newbie

    Reputation Points:
    May 28, 2008
    43 y/o
    Re: The Combined Carbogen Thread

    I have been trying to find Meduna's mixture for a long time now, but couldn't find where to get it, or how to make it, does anyone here know the answer for that? Considering that's something completely legal, I really don't understand why I couldn't find that information easily on the net (through Google, that's what I used).
  10. bananaweed

    bananaweed Newbie

    Reputation Points:
    Jul 20, 2007
    Re: The Combined Carbogen Thread

    1. Oxygen generator: KNO3 = KNo2 + O2 (need temperature to melt KNO3)
    2. CO2 generator - it's very symple - the simplest is a dry ice wich is a CO2 itself. Or baking soda + citric acid.

    Take a big PET bottle full of water, turn it upside-down and put in a jar of water. Put the plastic tube from the O2 generator to bottle and bubble the oxygen into it. When the gas fullfilled about one third of bottle volume - remove the tube with oxygen and replace it with tube from the CO2 generator and fill the remaining volume of the bottle. Here you go - you have about 1.5-2.5 litres of magic mix.

    PS - it's for the volume ratio, if 30/70 ratio is for the mass - volumes will be different.
  11. Terrapinzflyer

    Terrapinzflyer MDMA, RC & News Forums Platinum Member & Advisor

    Reputation Points:
    May 10, 2009
    from U.S.A.
    the current Erowid Extracts (November 2009) has an excellent article on Carbogen, with experiences from a group trial of this substance. An interesting read.

    Last edited: Nov 2, 2010
  12. torachi

    torachi Palladium Member

    Reputation Points:
    Apr 6, 2010
    from U.S.A.
    Is carbogen used in any industries? Does it have other applications other than as a 'panicogen'?

    Can anyone vouch bananaweed's method, or have any simpler approaches?

    also...can Para's post be edited for easier readability? It's a great post, but full of random brackets and numbers. The references could still be listed. This being the best thread on carbogen info, it should be clean.
    Last edited: Jan 26, 2011
  13. rasselas21

    rasselas21 Newbie

    Reputation Points:
    Mar 5, 2012
    from earth
    Re: The Combined Carbogen Thread

    It seems that above you're filling 1/3 of the PET bottle with O2 while filling 2/3 of the PET bottle with CO2... thus leading to a mix of 33% Oxygen and 67% Carbon Dioxide (which would be a potentially LETHAL combo)?!? So rather, shouldn't we be filling (a little more than) 2/3 of the bottle up with O2 and (a little less than) 1/3 of the bottle up with CO2?

    KNO3 is Potassium Nitrate, a type of SaltPeter (solid).
    KNO2 is Potassium Nitrite, a poisonous nitrite salt (solid).
    Na3C6H5O7 is (Tri)sodium citrate [aka sour salt] is a food additive.

    H3C6H5O7(aq) + 3 NaHCO3(sol) → 3 CO2(gas) + 3 H2O(liq) + Na3C6H5O7(aq)
    So an aqueous solution of citric acid combined with baking soda produces carbon dioxide, water, and trisodium citrate in aqueous solution.

    Mechanism: the reactions produce a desired gas in addition to other liquids, solids, and solutions... only the gas will rise (straight up) through water to fill the PET bottle.

    It's noted previously that dogs can live on 20% O2 and 80% CO2 for 10 minutes... and that, though dangerous, such a ratio can be psychedelic (via the Shulgin ancedote) but a simple correction of the above TEK should prove MUCH safer.

    ALSO... I'm thinking that collecting the gas in a small trash bag (which should expand to receive and hold the bubbling gas far easier than a balloon) could be useful, as the bag could first be evacuated of "normal air". Further, the bag could then be inhaled from directly (though inelegantly) through their mouth IF one were to remember to exhale through their nose. So, IF one were to choose a properly small bag (equivalent to, say, 20 breaths)... then would it be safe for an individual to self-administer the Carbogen???

    What would be the worse that could happen? A little safer (and much more congenial) approach would be to first transfer the air from the garbage bag to a large balloon. If one then began to have any problems at all, this would likely result in the balloon (of gas) falling/escaping from the lips and fingers, and an abortion of the negative effects. One WOULD need to make sure their bag/balloon was not overly-filled resulting in too many continuous inhalations.
    (By the way, a typical plastic grocery bag seems to hold about ~10-15 breaths).

    PS - does anyone know how much CO2 is exhaled through the breath? I'm surprised that only ~0.5 percent of the atmosphere is CO2 and that 20% is O2... it seems that plants survive on very little "breathable air" compared to animals.

    PPS - Notice the importance of not simply following TEKs and dosage guidelines without proper and prior thought, consideration (for safety), and research. That's better info IMO than knowing how to produce Carbogen, etc. I know it's easy to make a typo, or have one's speculation mistaken for fact... so no blame going out, but rather a warning, and a thanks for the excellent TEK idea.

    rasselas21 added 35 Minutes and 9 Seconds later...

    Carbogen can describe any mixture of CO2 and O2 ranging from 1.5%-50% CO2... thus I would think there would be industrial applications (such as in metallurgy?)... but could find no references or vendors for non-medical uses.

    Would it be possible to create or use a chemical that would biological mimic Carbogen by triggering the proper/useful receptors? There are many unwanted biological effects that could potentially be bypassed, by using something other than CO2 itself... the previous posts seem to imply that the brain triggers a response based on PH levels, rather than detection of CO2 itself, correct? Would the inhalation of another acidic gas also produce similar results? Well, I think that any acidic gas would produce acid-blood levels (though nonetheless perhaps less toxic than CO2), and so should be avoided. Perhaps there are other detection methods of CO2 in the body, which would be more amenable to safe mimicry.

    PS - to reiterate a word of caution: extended inhalation of highly oxygenated mixtures may cause blindness (via renal faliure). Such mixtures are also extremely flamable, and all sparks (even static electricity?), embers (even stop-top burners?), and flames (so no flame-wars please!) should be kept away.
    Last edited by a moderator: Mar 9, 2012