Talk:Naloxone

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Citation about naloxone's side-effects should be inserted. The side-effects listed here can all be caused by withdrawal syndrome, except the 'infection', which is a side-effect I for one have never heard of for naloxone. It can be caused by subcutaneous/intramuscular/ injection of grinded down Suboxone, but not of naloxone itself. So either a good citation for these side-effects is needed, or some serious editing should be underway.

Dr evi 666 08:41, 30 August 2007 (UTC)

The stuff about naloxone's activity in Suboxone is mostly untrue. Naloxone does nothing to prevent IV or intranasal abuse, except by scaring people away from trying it. Buprenorphine's much higher affinity for opioid receptors makes the naloxone irrelevant.

Most of the side effects/withdrawal symptoms attributed to naloxone are in fact caused by buprenorphine itself. Naloxone is hardly absorbed sublingually. Buprenorphine, with or without naloxone, will cause someone on pure agonist opioids to experience withdrawal. Also, naloxone will not cause someone on buprenorphine to go into withdrawal.

Flopster2 12:16, 21 October 2007 (UTC)


@ Flopster2: Naloxone is added to the suboxone tablet for scaring people, that much is true. But there is a rationale behind all this: because of the large difference in bioavailability in different modes of administration; if a drug user takes suboxone sublingually so little naloxone is absorbed (due to low bioavailability of naloxone), no effect will be noticed. However, if it is injected intravenously or intramuscular, the naloxone in the tablet (now much more naloxone is available) causes an acute withdrawal syndrome. See also the following articles JOHNSON RE MCKAGH J: Buprenorphine and Naloxone for heroin dependence. Curr Psychiatry Rep (2000) 2: 519-526 and STOLLER KB BIGELOW GE WALSH SL STRAIN EC: Effects of buprenorphine/naloxone in opioid-dependent humans. Psychopharmacology (Berl) (2001) 154: 230-242.

And on a minor note: naloxone IS able to reverse several of buprenophine's effects, such as respiratory depression, analgesia and sedation albeit in high doses (much higher than in the suboxone tablet). I'm not sure how the mu-opioid receptor changes with addiction, but I reckon addicted people on buprenorphine (and possibly many more drugs acquired illegally) could go into withdrawal from naloxone. Dr evi 666 14:44, 1 November 2007 (UTC)

I suppose this would be original research, but it really doesn't cause any withdrawal whatsoever either intranasally or intravenously (tested in both opioid naive people and buprenorphine maintenance patients). Both of those routes feel more effective overall than sublingual, but because there's no rush, IV isn't worth the risk. Sure it will cause withdrawal in anyone on other opioids, but buprenorphine alone will do that. I have read reports to this effect online, and if I come across them again I'll cite them here. --Flopster2 22:55, 4 November 2007 (UTC)

The Stoller paper is about hydromorphone dependent people. In the "Nondependent" section of the Johnson paper, it states that "the combination (1:1 ratio) attenuated the acute opioid agonist effects." Note that the amount of naloxone used is much greater than in Suboxone. In the "Dependent" section, it states that those on Suboxone maintenance chose money over IV buprenorphine/naloxone (which is quite understandable), but it doesn't mention withdrawal. For those on all of the other opioids tested, it did cause withdrawal. Neither of these papers say anything about precipitated withdrawal due to buprenorphine alone, but there are plenty of others that do, e.g. [1], [2].

In [3], a pretty large dose of naloxone given a day after the last dose of a relatively low amount of buprenorphine produces withdrawal. [4] indicates that IV buprenorphine/naloxone, while less desirable than buprenorphine alone, produces similar effects. The difference in perception of the effects decreases with time, presumably as the naloxone wears off. While [5] mentions precipitated withdrawal in some abusers, it does not indicate whether they were on other opioids at the time. Inclusion of naloxone does succeed at making IV Suboxone abuse less attractive than IV Subutex.

It appears that, when used IV, the naloxone Suboxone attenuates the buprenorphine's effects somewhat and may contribute to (or cause) the withdrawal experienced by those dependent on full agonists. The dose of naloxone is insufficient to cause withdrawal, and the increased bioavailability of buprenorphine likely makes up for any antagonist effects. I'd like to see a study comparing desirability of SL vs. IV in opioid naive or buprenorphine maintenance patients. It's arguable which method is more effective, but IV (or IN) use does not lead to withdrawal. --Flopster2 00:50, 5 November 2007 (UTC)

I agree. Still, all so-called naloxone side-effects are not related to the drug itself and therefore irrelevant. Dr evi 666 (talk) 09:33, 21 January 2008 (UTC)

Contents

[edit] Naxolone and Childbirth

I removed the line: "In one experiment, women treated with naloxone reported higher pain levels during childbirth than women not so treated[citation needed]" Because it has been dated as uncited since july 2007, and seems very unlikely given the ethical consideration involved.Halogenated (talk) 00:13, 20 January 2008 (UTC)

[edit] Naloxone and NMDA receptor

As naloxone is a mu-opioid receptor antagonist, can someone explain why it should counteract the effects of ketamine, a NMDE receptor antagonist? Doesn't seem very plausible. Dr evi 666 (talk) 09:33, 21 January 2008 (UTC)

Ketamine is far from a selective NMDA antagonist it has a numerous set of binding sites including the mu opioid receptor - a pubmed search for ketamine mu opioid will find the relevant research. Mu opioid receptors are also involved in facilitating reward in general and mu opioid antagonists can reduce the rewarding effects of some drugs that have no direct affinity for that receptor, for example chocolate, cannabis and psychostimulants such as amphetamine and cocaine. I do not know where you came to the conclusion that ketamine is a selective NMDA antagonist, if it did not have an affinity for the sigma receptor it would be neurotoxic and ketamine is a strongly neuroprotective drug - particularly used in situations like head injury to prevent neuronal damage, it is also anti-inflammatory and can reduce brain swelling. Again if you want references you can search pubmed because this is all quite common knowledge and I don't particularly feel like searching for it right now. —Preceding unsigned comment added by 78.145.92.251 (talk) 01:18, 22 February 2008 (UTC)

"common knowledge" is quite an easy term, isn't it? I never used the word selective, it's just that the involvement of MOR in ketamine's pharmacological actions is so small, I doubt addition of naloxone will counteract them. I merely reacted to the fact that references are needed for the statement regarding naloxone and ketamine in the main article and I could not find appropriate ones. But you did not or could not supply them either. On top of that, there is evidence for neurotoxic effects of racemic ketamine on the developing brain, as the following references will show:

  • Ke JJ, Chen HI, Jen CJ, Kuo YM, Cherng CG, Tsai YP, Ho MC, Tsai CW, Yu L.Mutual enhancement of central neurotoxicity induced by ketamine followed by methamphetamine.Toxicol Appl Pharmacol. 2008 Mar 1;227(2):239-47. Epub 2007 Nov 1. PMID: 18076959 [PubMed - in process]
  • Soriano SG, Anand KJ. Anesthetics and brain toxicity.Curr Opin Anaesthesiol. 2005 Jun;18(3):293-7.PMID: 16534354 [PubMed]

I would not be as quick to say ketamine is not neurotoxic... Dr evi 666 (talk) —Preceding comment was added at 11:44, 25 February 2008 (UTC)

[edit] addiction...ology...

"only certified addictionologists (physicians specializing in the treatment of drug addiction and dependence)"

Is it just me or did the person who wrote that just make it up on the spot... where exactly does one go to train to become an "addictionologist"? surely the term 'addiction specialist' is the appropriate term, additionologist makes about as much sense as drugologist, brainologist and fruitologist. If I am mistaken on this then do put me straight but that sounds bloody ridiculous to me. —Preceding unsigned comment added by 78.145.92.251 (talk) 01:08, 22 February 2008 (UTC)

[edit] Qualitative effects of naloxone versus naltrexone

Can someone who actually knows, say what the qualitatively different effects are between these two drugs? It is not obvious to the reader what they might be, as the drugs have such similar modes of action —Preceding unsigned comment added by Woodcore (talk • contribs) 17:01, 27 February 2008 (UTC)

[edit] Removed effects with other drugs...

The implication, without any citation, was that Naloxone may be effective in reversing overdoses related to other recreational drugs, which seemed especially absurd since some of the drugs mentioned (PCP and Ketamine) work on vastly different receptors than opium does. The assertion, which shows up in other places, that it can also reverse the effects of salvia also seem without merit, atleast until someone can find a peer reviewed report that establishes such. SiberioS (talk) 03:48, 21 May 2008 (UTC)

Great!! this is what I was hoping to do after someone replied to my post on the NMDA receptor. To my knowledge, no peer reviewed report is available that shows the use of naloxone for PcP and ketamine. Glad this misunderstanding has been taken care of! Dr evi 666 (talk) 15:50, 3 June 2008 (UTC)