Newsgroups: alt.drugs From: jerry@teetot.acusd.edu (Jerry Stratton) Subject: Re: Nitrous oxide (be patient) Message-ID: <1994Jan12.010623.13434@teetot.acusd.edu> Date: Wed, 12 Jan 94 01:06:23 GMT [quoted article deleted -cak] Blow me. Yes, nitrous does 'kill brain cells' although that's a pretty general statement. Both life and alcohol also kill brain cells. If you're truly interested in the medical aspects of recreational drugs, written for laymen, get the following two books, both, as far as I know, still in print (unlike the wonderful _Licit & Illicit Drugs_, which I tend to buy whenever I see it, just so I can give it to friends :*) FROM CHOCOLATE TO MORPHINE: Andrew Weil & Winifred Rosen. Make sure you get the 1993 edition. It's the one with the horrible sub-title "Everything You Need To Know About Mind-Altering Drugs". The sub-title's wrong, but it's still a good reference. A PRIMER OF DRUG ACTION: Robert M. Julien. I believe it's in the fifth edition right now, but I don't know. Here's the kind of stuff you can expect to find in these books: Robert M. Julien: "Occasionally, certain anesthetic agents become misused drugs. Nitrous oxide is an example. A gas of low anesthetic potency, it is incapable of inducing deep levels of anesthesia if an adequate oxygen concentration is maintained. Nitrous oxide induces a state of behavioral disinhibition, analgesia, and euphoria. One of the problems occasionally encountered when nitrous oxide is used for recreational purposes is that, unless the compound is administered with at least 20 percent oxygen, hypoxia (decreased oxygen content of the blood) can be induced. But in order to achieve high enough concentrations of nitrous oxide to get a good behavioral effect, concentrations of 50 percent or greater must be inhaled. If such concentrations are mixed with room air, inhaled oxygen concentartions drop to low levels and the hypoxia may result in irreversible brain damage." (In other words, don't use it in your vw bus :*) Weil & Rosen: "Physicians and dentists have long considered nitrous oxide to be a safe pharmacological agent. Nevertheless, there is some evidence that excessive or prolonged use of it can damage the bone marrow and nervous system by interfering with the action of vitamin B-12. Moreover its use in nonmedical settings presents several hazards that users should keep in mind. Breathing it directly from pressurized tanks is dangerous for two reasons. First, gas flowing from such tanks is very cold -- cold enough to cuase frostbite of noses, lips and (most serious) vocal cords. Being anesthetized, a user may be unaware of such injuries until too late. Second, because nitrous oxide does not support life, it should be mixed with oxygen if it is to be breathed for more than a few minutes. At private parties, oxygen tanks are rarely supplied, and people have died of asphyxiation by breathing straight nitrous oxide through face masks. One way to avoid these dangers is to fill balloons from tanks and breathe from the balloons. 'Further, nitrous oxide rapidly leads to complete loss of motor control, and anyone who breathes it while standing will soon reel about and fall down. Therefore, it is unwise to try the gas unless one is in a comfortable sitting or lying position. Serious injuries have resulted from people inhaling laughing gas while standing in front of open windows, when driving cars (like your dad, HST), or when operating machinery. Others have been badly hurt by accidentally pulling heavy tanks of nitrous oxide over onto themselves (it's mine! all mine! you can't have any!) while intoxicated. 'People who breathe nitrous oxide for more than a few minutes at a time may experience nausea, especially if they have just eaten. They may also feel hung over for some time after. Addiction to nitrous oxide is a real possibility. Addicts may suffer serious mood and personality changes in addition to the bone marrow and nervous system damage already mentioned." Plus, it's lots of fun. (My opinion, again.) Jerry Stratton jerry@teetot.acusd.edu (Finger/Reply for PGP Public Key) ------ "Well, if you can't believe what you read in a comic book, what *can* you believe?!" --Bullwinkle J. Moose ============================================================================= From: chris@hacktic.nl (chris) Newsgroups: alt.drugs Subject: Nitrous Oxide Dangers Date: 12 Jan 1994 21:52:13 +0100 Message-ID: <2h1nubINNk66@xs4all.hacktic.nl> NITROUS DOES IT KILL BRAIN CELLS? In an earlier post I mentioned some scientific reports on the possible dangers of prolonged exposure to nitrous oxide. This elicited some reactions that focus around the definition of "prolonged exposure". How much nitrous taken in how much time will rot your nerves? To get an idea i will transcribe two case reports from a more recent nitrous horror story. At the same time it will give you an idea what "neuropathy" and "myeloneuropathy" looks like and what signs to watch out for when you are a nitrous regular. From: Stacey et.al (1992) " Methionine in the treatment of nitrous oxide induced neuropathy and myeloneuropathy" Journal of Neurology 239:401-403. Case 1 (quote) This 36-year old electrical engineer came to the emergency room complaining that he was unable to walk. Symptoms had begun 4 days earlier with "pins and neeedles" in both feet that gradually worsened and ascended to involve the knees and the fingertips. With worsening of the paresthesias (-no sense of touch or pain-) he noted difficulty in maintaining proper control of the movements of his arms and hands and trouble in walking. He also reported the sensation of electric shocks through his back and legs upon flexion of the neck. He denied bladder or bowel impairment but he had been unable to have an erection for the past week. His past medical history was unremarka- ble except for occasional abuse of alcohol in the past. However he denied any drinking of alcohol for the past 8 months. For recreational purposes he had inhaled two to three boxes of nitrous oxide, each box containing 24 cartridges, practically every day for the past six months. When first seen his general physical examination was completely unremarka- ble. The neurological examination showed hyperesthesia and hyperalgesia in the lower extremities up to the knees. He had severe bilateral sensory dystaxia and could only stand with support. (-More Neurological and Blood statistic Stuff Deleted- ed.). Intramuscular B12 injections were started and during the following days his hematological status inproved, (-apart from neurological symptoms, the functional B12 deficiency caused by N2O also produces megaloblastic anemia,- ed.) although his neurological condition continued to deteriora- te. The paresthesias ascended to the nipples and he developed fecal and urinary incontinence. (- stuff deleted-) Four weeks later he began to improve and four months after the onset of the symptoms, and his last use of nitrous oxide he could walk with some hesitation and had completely regained bowel and bladder control and sexual function (-stuff deleted-). Case 2 This 32 year old woman was admitted tho the neurology service for inability to walk and paresthesias in her limbs and trunk. Her symptoms began 3 weeks prior to admission with a "tingling" sensation in the soles of her feet, trunk and hands. Her gait bexcame progressively less steady and the day prior to admission she had an episode of urinary incontinence. Her past medical history was significant for bulimia and occasional intranasal use of cocaine. for the previous 3 months she had inhaled nitrous oxide for recreational purposes, up to 200 cartriges a day, three to four times a week. (-stuff deleted, similar neurological signs as above, some antisocial behavior). (end quote) What this shows is that these people really did a lot of nitrous, say 300- 400 cartridges a week, for a few months in a row to develop these really nasty symptoms. But it also shows that people who do such things do exist ( can you believe it?) For the really health conscious among you (a contradiction in terms?) if you "must" do nitrous for a longer period be sure to take high doses of folic acid (is also depleted from your body as a result of functional B12 deficiency ) and vitamin B12. (No injury NOT guaranteed, but it might help) Also, but less well known, the state of B12 deficiency caused by regular use of nitrous oxide produces hyperhomocysteinemia, an accumulation in the blood of the amino acid homocysteine. Hyperhomocysteinemia is a risk factor for vascular disease of all sorts. Furthermore, hyperhomocysteinemia, B12 deficiency and folic acid deficiency early in pregnancy all increase the risk of getting a child with a neural tube defect (spina bifida and anencephaly, childeren with no brains or open spinal cord). If you are a woman, planning to get pregnant or just "at risk of getting pregnant", nitrous is a bad idea. If youre interested in this literature contact me. More literature on neurological aspects of nitrous use: Pulsson (1979) "Recreational" misuse of nitrous oxide, J. Am Dent. Soc. 98:410-411 Sahenk et al.(1978) "Polyneuropathy from inhalation of N2O cartridges through a whipped cream dispenser" Neurology 28:485-487. Chris ( chris@hacktic.nl ) ============================================================================= Newsgroups: alt.drugs From: bagg@ellis.uchicago.edu (matthew john baggott) Subject: Re: Nitrous.. facts vs. myths Message-ID: <1993Mar23.214307.19900@midway.uchicago.edu> Date: Tue, 23 Mar 1993 21:43:07 GMT [quoted text deleted -cak] I've been meaning to write up a FAQ about this and have done some preparatory reading, so I'll take a shot at a first-pass answer: First, there are the dangers which accompany the inhalation of any compressed gas (making sure you get enough air, making sure you don't freeze your lips or inflate your head, making sure you are sitting down and won't hurt yourself if you get dizzy). Second, there are the health effects specific to nitrous oxide. There have been reports of immunological and reproductive disturbances in professionals who are chronically exposed to nitrous oxide. The immunological disturbances are documented by Peric et al (1991) _Anaethesia_ 46: 531-7. Apparently anaesthetic personnel had been complaining about weakness and recurrent infections and decreased peripheral blood leukocyte counts has been found. The operating rooms were found to be improperly ventilated, causing nitrous oxide and halothane (another anaesthetic) to remain in the air. Even after a 3-4 week holiday, some personnel has decreased B lymphocytes and increased red cell count, haemoglobin concentration and haematocrit and other disturbances. I don't have a reference handy for the reproductive disturbances, but the study basically found that women who were chronically exposed to nitrous had difficulty becoming pregnant. It should be noted that these health effects are the result of CHRONIC exposure; a single balloon at a Dead show (or a single visit to the dentist) is unlikely to be a problem for a healthy individual. Aside from its psychopharmacological actions, nitrous oxide has one other (known) significant metabolic action: it interacts with vitamin B12. This was first reported in an in vitro study in 1968, but didn't really receive notice from anaesthesiologists until ten years later (because medline didn't exist yet :-) ). In 1978, however, Amess et al showed that 24 h of nitrous oxide administration caused interference with DNA synthesis in humans. Since then, the interaction between nitrous oxide and B12 has been better characterized. Basically, B12 is a bound coenzyme of methionine synthase and has a tetrapyrrole rings with a monovalent cobalt at the center. The cobalt functions as a methyl carrier in a transmethylation reaction. Nitrous oxide converts the cobalt from the monovalent form to the bivalent form. As a result, methionine synthase activity is inhibited. Recovery is believed to require absorption of new unoxidized B12 (and synthesis of new apoenzyme). Humans seem to be far more resistant to complications from this than rodents. I don't have the energy to go through the various published studies at this point, so I will quote from Nunn's "Clinical Aspects of the Interaction Between Nitrous Oxide and Vitamin B12" (1987), _Br. J. Anaesth._ 59: 3-13. It seems likely that in man, in contrast to the rat, exposure of less than 30 minutes will not cause any measurable change in methionine synthase activity. In combination with a wealth of clinical experience, this suggests that there is no special hazard for short exposures to nitrous oxide. There is a variable response to exposures lasting between 30 minutes and 2 h. However, it now seems likely that exposures of more than 2 h are likely to cause intereference with hepatic methionine synthase activity. The paucity of human data makes it more difficult to say how long an exposure is required to cause significant intereference with DNA synthesis. It is likely that there will be considerable individual variation and results obtained in healthy patients cannot be extrapolated to the patient who is seriously ill. Nevertheless, it seems likely that, once methionine synthase activity is inhibited, it will remain so for days. With respect to repeated exposures to nitrous, be aware that this effect can build up (Nunn gives "intervals of less than 3 days" as a cut-off). So, go easy on the "hippie crack," people! Mandatory nitrous horror story: Layzer (in (1978) "Myeloneuropathy after prolonged exposure to nitrous oxide," _Lancet_ 2:1227) reports a case of 15 people who had been inhaling nitrous oxide for long periods of time and developed a condition resembling subacture combined degneration of the cord, whatever that means. I would suggest that the following types of people in particular avoid exposure to signficant amounts of nitrous: Pregnant women: since nitrous oxide is a known teratogen in rodents, acting by depleting folates and partially reversible by oral folinic acid, we can expect a similar syndrome in humans. Vegans who don't take B12 supplements: although documented cases of vegans with B12 decifiencies are scarce, theories on nutrition indicate that vegans are unlikely to get as much B12 as other groups of people. Individiduals with healing wounds, infections, or immunological disorders: I'm throwing this recommendation in based on a "better safe than sorry" policy. Short-term exposure to nitrous oxide is unlikely to be a problem, but why not play it safe? And BTW I did find a reference on sexual ideation during nitrous oxide, which is a topic that came up some time ago. More on that when I actually get the article. --Matt Baggott, bagg@midway.uchicago.edu >-- > kkwast@cs.utexas.edu (Kevin A. Kwast) "The computer is your friend."