Talk:Equianalgesic/Archive 1

Equianalgesic

New Content

This article was a stub, so I added some new content that I felt was useful. This is my first attempt at writing an article, so it's far from perfect. Please review my WP:WORDS, any constructive feedback is appreciated. Mostly I'm concerned about the writing style and section headings. I think the information is good, but I'm more of an essay writer so if anyone wants to wikify it I'd love to hear your suggestions and edits. Cheers, DubiousIrony ^yell 00:17, 14 January 2011 (UTC)

Welcome to Wikipedia, and yes I'll give it a shot. --Tryptofish (talk) 22:09, 14 January 2011 (UTC)

Rename and Merge

Would it make sense to rename this page to Equianalgesic chart? --Tryptofish (talk) 22:32, 14 January 2011 (UTC)

I agree, this article is about the charting/method of comparison, not the equivalence of various opiates. Therefore the tool should be the title for the page. Also major concern here is not enough wikilinks to this page. If this is a fundamental (hence notable tool) for use in medicine should be wikilinked from articles covering areas such as opiates, pain management, analgesia, acute/chronic pain, palliative care.

Ok start to the article - once basics started out, would work on history of these charts, and science/research that they are based on, with references of course. Thanks Cheers Lethaniol 00:42, 15 January 2011 (UTC).

Article might be best merged with Opioid comparison as a new Section. Later can have its own page if becomes detailed enough. Main advantage of this, is people who find one page, will get both sets of info on one - a comparison of opiods (needs to get proper refs) and how they are compared and with what tool. Ask if you need help if you want to do this. Cheers Lethaniol 02:07, 15 January 2011 (UTC)

Article name I agree about the name change to 'equianalgesic chart'. I edited the article as it was when I stumbled across it, but I too thought that a name change might be in order. Equianalgesic chart seems to be a known term (Google) although 'narcotic conversion chart' has about 10x the hits. Perhaps a name change to 'narcotic conversion chart' or 'opioid conversion chart'? What do you guys think?

Notability I disagree about merging it into opioid comparison. This article elaborates on an important medical concept and the topic is sufficiently notable to stand alone. Google Books has 6.6k results on equianalgesic (equianalgesic dose, equianalgesic chart, etc.) and about 300 on equianalgesic chart. Google Scholar also has lots of hits on terms like equianalgesic chart/dose/calculation. To be honest, I think opioid comparison should be merged into this article. I'm not sure what the policy on this is, but the opioid comparison article seems to exist solely for the equianalgesic table it includes and does not discuss the actual concept of opioid comparison at any length. Thoughts?

Inbound links The reason for few inbound links is mostly because of the different names this topic is addressed by (equianalgesic chart, narcotic conversion chart, equivalent dose, opiate conversion, etc.) I will work on skimming relevant articles and linking to this article when appropriate.

Thanks to everyone who cleaned up the article after my edits. Lethaniol, your explanation of dose accumulation is infinitely better than mine. I knew 'dose stacking' wasn't the term I was looking for but I decided that since I was having a brain fart, and this is Wikipedia, another user will see what I mean and explain it :) Cheers, DubiousIrony ^yell 03:35, 15 January 2011 (UTC)

If we agree that Opiod Comparison and Equianalgesic chart (or maybe Analgesic Comparison) should be merged then it is just a matter of deciding what page to decide to merge to. I prefer Opiod Comparison because to a lay person this will make immediate sense. The only reason I clicked on Equianalgesic before was because I had no idea what it meant.

In such a page, would broadly structure about why we compare, how we compare and finally a comparison table (heavily referenced). So actually the information on this page would come before the Opiod comparison data. Also would make sure pages such as this, Equianalgesic chart, analgesic comparison all redirected to the new merged page.

If we are happy with this then can look to merge soon.

And no problem with rewording 'dose stacking' - that is how wikipedia is meant to work :)

Cheers Lethaniol 12:47, 15 January 2011 (UTC)

If we do a merge, I'd merge the other page into this one, not the other way around. The other page is basically just a chart, whereas this, although currently only at start level, is actually a content page about the subject. I think I'm sold on having whatever title we settle on include the word "chart". And I kind of like the idea of Analgesic comparison chart as being the most general, least jargony, and potentially open to non-opioid analgesics. Do these things ever include NSAIDS, for example? And we can certainly have redirects from all the alternative names. --Tryptofish (talk) 21:58, 15 January 2011 (UTC)

I agree that the two articles should be merged, specifically that 'opioid comparison' should be merged into this article per Tryptofish' reasons. I also agree that we need to rename this page. I spend some time on Google Books/Scholar and the name narcotic conversion chart is the most popular on Google Books (27.9k quotes) and opioid conversion chart second most popular (19.8k) Alternatively, analgesic comparison chart has only 492 hits. For this reason, I think a 'conversion chart' suffix would be best. I favour 'conversion' over 'comparison' as (IMO) it portrays a clearer purpose/intent (to convert from one opioid to another instead of just comparing their effects) and is also the term preferred by many sources. I like the idea of a non-opioid analgesic comparison in principle, but I think it would be difficult to implement as opioids are so well-researched and similar to each other that most literature only focuses on narcotic conversion (I couldn't find a single NSAID conversion chart.) I think Wikipedia prefers the term 'opioid' over 'narcotic', so for all the reasons mentioned above I propose the following:

• Move (rename) this article to opioid conversion chart.
• Merge 'opioid comparison' into this article.

I'd like to hear your guys' comments! DubiousIrony ^yell 15:21, 16 January 2011 (UTC)

• Support. We could do the rename any time. We would need to post a further discussion before doing the merge. --Tryptofish (talk) 19:18, 16 January 2011 (UTC)

• Support. Merging these two articles into either opioid conversion or opioid conversion chart.

If agreed by us three here, would need to follow procedure, and will take 1-2 weeks to confirm - can work on the articles in the mean time - even working on the merged page in namespace. As part of the procedure we can ask for input on the title of the merged page. Personally I think narcotic has such negative connotations that I would really like to steer clear of using this. Ofc can have redirect from narcotic comparison etc... . I will put up merge templates tomorrow if someone else has not already (i.e. will usee Template:Merge) see more information in general @ Help:merge. Cheers Lethaniol 21:51, 16 January 2011 (UTC)

Note by using a template such as: Merge |OtherPage1 |OtherPage2 |target=OtherPage3 |discuss=Talk:OtherPage#Merge discussion |date=January 2011, can discuss move and merge at same time, no point in separate discussions for them unless someone requests it, which is unlikely. Actually I'll just make the templates now. Cheers Lethaniol 21:58, 16 January 2011 (UTC)

I feel the name of "Opiod Comparison" should be kept as the name of any resulting merged article. It is becoming increasingly hard to find info quickly on the Wikipedia as details get merged into denser and denser 'omnibus' articles that require much more keyword searching to locate. I likely would never have found this chart (which I badly needed at the time ) if it had it been buried in some exotically-named omnibus article. — Preceding unsigned comment added by 8.26.249.120 (talk) 01:33, 20 October 2012 (UTC)

External link awful

The Narcotic Equivalence Converter is wrong to the point of being potentially dangerous and should be removed. AreThree (talk) 09:10, 27 July 2011 (UTC)

Done. --Tryptofish (talk) 19:43, 28 July 2011 (UTC)

Thank you... I didn't want to slash what was the only external reference. I have also done work on Opioid_comparison and that is what lead me to this article. I will try to look for some better sources for both of these articles and contribute, since I have an unfortunate insider's view to pain management. AreThree (talk) 22:09, 30 July 2011 (UTC)

Opioid comparison

IMPORTANT- PLEASE NOTE- Poor to the point of being dangerous!!

+++++This topic is of great clinical relevance. Its subject matter is highly complex. The entry has started, however, at present the 'article' needs completely rewriting... Now! If this article grows from this, hotch-potch, guessmiquick, anecdotal tripe, we shall at best, do both the subject matter, & encyclopedia a great injustice. 1}. Opiate Comparison chart which uses NSAIDS as precedents. 2}. OC chart written without any knowledge of clinical significance, 3}. A distinct lack of opiates in regular clinical use. 4}, A basic outline of agonism & antagonism in relation to receptor sites 5}, Do you need help on this one??????

PS To the chap asking about DIM & Methadone. It doesn't. Why? Heroin (DAM) has very different pharmacodynamics, pharmacokinetics, favoured routes of administration, dosages (chronic & acute). However, I will try to answer what I must presume you are asking. Methadone, a long-acting (half-life>24 hrs) opiate usually administered orally in the so-called 'detox programmes'. A synthetic invented by the Germans during WWII, due to the shortage of morphine. Morphine is the standard drug by which all other opiates are measured by (not codeine). Morphine, like diamorphine (diacetylated morphine i.e heroin), both have a high first-pass metabolism), i.e they are absorbed by the stomach but the liver's microbial enzymes attack ~80%(F.P).Thus their use medically & non-medical, are injected. This is not the case with methadone. Hence, one reason stated for its preffereded use as a detox agent. Listen! Check out the drugs on Wiki independently, they are well-written, & read around. Begin with Heroin is not like methadone because.....?

Respectfully,

Prof Mad ++++++++--Profmad (talk) 20:39, 13 April 2010 (UTC)

The table seems to be a straight copy from the reference, which itself references wikipedia, and also states that it is not a reliable source of information! --Greg

Diacetylmorphine

where does diacetylmorphine (heroin) fit on this chart also methadone? —Preceding unsigned comment added by 71.182.109.139 (talk) 04:30, 9 March 2010 (UTC)

Opioid

This page should be called opioid comparison as this is the correct usage of the term. "Opiate" only refers to substances obtained directly from the poppy - codeine and morphine

--Axxaer (talk) 13:11, 30 December 2010 (UTC)

And diacetylmorphine and methadone can easily fit on this chart in regards to relative potencies.

--Axxaer (talk) 13:15, 30 December 2010 (UTC)

Moved. If you have any problems with it let me know

--Axxaer (talk) 13:45, 30 December 2010 (UTC)

Aspirin dosage

I don't think it is responsible to show what would be getting close to an overdose of aspirin (3600 mg) for the comparative dose to 10mg morphine, as some eager fool may try and take that much aspirin in the hopes that it would feel like morphine. Besides, aspirin would have long inhibited all the COX enzymes in a person's body before that dose so the pain relief would not be equivalent to 10mg of morphine. It is purely a mathematical calculation. For these reasons I think it better to say "nil". Comments?

--Axxaer (talk) 13:43, 30 December 2010 (UTC)

Codeine columns

It is my opinion that the codeine columns should be deleted, as it is just duplicate information, and as Prof Mad said, all opioids are compared to morphine as standard, not codeine. Thoughts and comments please. If no one disagrees I will delete it within a month. Respectfully --Axxaer (talk) 10:29, 2 January 2011 (UTC)

11:34, 4 March 2011 (UTC)~PROFMAD11:34, 4 March 2011 (UTC)Thank you for acknowledging this point. The chart does need re-editing. I will do another table, which may then be further edited by fellow 'Wiki's', followed by replacement of the main article chart. I think it necessary to remove NSAID's, since these are not opiates. The chart is regarding relative pain-control effectiveness, (which differs to opiate transfer change, particularly in/for dependency). Ketamine, hyoscine, alcohol & nitrous oxide, all have analgesic effects, but have no place in such a chart, it being an OPIATE COMPARISON CHART (For Pain)11:34, 4 March 2011 (UTC)PROFMAD11:34, 4 March 2011 (UTC) — Preceding unsigned comment added by Profmad (talk • contribs)

I went ahead and deleted the codine comparison columns. AreThree (talk) 09:00, 27 July 2011 (UTC)AreThree

Tramadol

Perhaps tramadol should have a footnote clarifying that it is a prodrug. Tramadol itself is very weak. It's metabolite, O-desmethyltramadol, is the more potent μ opioid agonist. 100 mg of tramadol hcl is metabolized into O-desmethyltramadol which precipitates analgesia similar in strength to 100 mg of codeine or 10 mg of morphine. --Rotellam1 (talk) 20:04, 30 May 2011 (UTC)

changed the reference to prodrug in the chart AreThree (talk) 09:00, 27 July 2011 (UTC)AreThree

Math wrong in chart? Poor source? Math is hard!

I am a bit confused and concerned. I don't think that the math is correct in the comparison chart.

For instance, if Oxycodone is 1.5–2 times the strength of Morphine, the equivalent dose for 10mg of Morphine isn't 4.5-6mg ... it would be 5-6.66mg wouldn't it? And if Levorphanol is 8 times the strength of Morphine, the equivalent dose for 10mg of Morphine isn't 0.8 mg ... it would be 1.25mg? Or am I not understanding the conversion correctly?

Additionally, the reference that is quoted says ITSELF that it is single-sourced and NOT to be quoted! Opioid Comparison at http://www.pharmer.org/forum/discussion-prescription-and-otc-meds/opioid-comparison AreThree (talk) 03:36, 21 July 2011 (UTC)AreThree

Fixed the math. I agree that the article is in desperate need of reliable sources. – Acdx (talk) 20:46, 25 July 2011 (UTC)

I have an issue with the math, also - well, at least it looks like it's an issue of math, if there is some pharmacological reason please let me know - specifically dealing with morphine. I don't understand how if morphine has an oral bioavailability of approx 25%, then with a bioavailability of 100% I don't get how the potency of IV morphine is 3 times stronger, rather than four. Could someone let me know if this is just bad math, or if there is a specific reason could you explain it for me? (01/26/2013 03:53 UTC) Prophet Samuel (talk)prophetsam

Methadone Potency

It says Oxycodone is 1.5-2x the strength of morphine, yet says Methadone is only half the strength of morphine.This is the most ridiculous thing I've ever read, and honeslty the entire chart is off. Methadone is at least the same potency as oxycodone, and in chronic users, is atually more potent.and to say it takes 20mg of Methadone to equal 10mg of ORAL morphine is laughable.Now, if it was IV morphine it would be different, but oral is only around 20% the strentgh of IV.As such, most people would literally not even get any analgesia off of a 10mg ORAL morphine dose, but would possibly be nodding and sick from being high on 20mg Methadone.Someone fix this, otherwise there is NO REASON WHATSOEVER to have a chart like this up, if it's data is completely and inexplicably wrong... — Preceding unsigned comment added by 24.98.250.155 (talk) 01:21, 12 August 2011 (UTC)

The table of equivalents in the article is not sufficiently labeled. The column parenthetically labeled 10 mg morphine refers to injected morphine, which is about four times as potent as oral morphine, because oral morphine is only about 25% absorbed, as noted in the table. — Preceding unsigned comment added by 66.208.218.141 (talk) 20:57, 16 April 2012 (UTC)

Fixing this article.

I changed methadone to 3-4x the strength.Note that this is speaking exclusively of ORAL dosing.You see, Methadone has a great oral bioavailability, averaging around 80% and sometimes being 90%.Conversely, Morphines extremely heigh first pass metabolism yields an obnoxiously low bio-A, around 20%, though it varies.As an educated person on this subject, Methadone is definitely more potent than morphine mg-per-mg, and since it also has 3 or 4 times the bio-a of when taken orally, you ultimately get MUCH more effect.Though again, if this chart we're speaking of IV/IM, it would be closer, MD probably isn't more than 2x as strong injected, but as long as it's oral, this is how it stays.I honestly suggest the chart be expanded though to include IV, because when you're talking 15-20% of a drug by mouth vs 100% IV, it's a HUGE difference, particularly when IV is the gold standard for Morphine, and morphine is the gold standard for pain relief.I might do it myself but it's all about time... — Preceding unsigned comment added by 24.98.250.155 (talk) 01:40, 12 August 2011 (UTC)

Couldn't agree more, it is ridiculous to put Methadone between Pethidine and Hydrocodone, it needs to moved above morphine(oral) for starters and just off hand i believe it is stronger than oxycodone and possibly stronger than morphine IV. — Preceding unsigned comment added by 86.7.13.168 (talk) 18:33, 15 August 2011 (UTC)

Bupe

The article says "all BA's are listed oral unless otherwise specified" well that is incorrect, the buprenorphine figure is obvioulsy not oral, because it has a BA of less than 10% via the oral route. Thus, the MOA being used for the comparison should be listed. I am honestly not sure what the MOA used is; I know IV is AT LEAST 40x the strength of oral morphine, but I am not sure if it is any more than 40x. Conversely, I doubt the sublingual administration(which is the intended route) is quite that strong. So I guess I shall try to figure out which MOA the figure refers too, and then alter the article appropriately. I may also add a footnote explaining Buprenorphine has an even lower BA orally then either morphine or diamorphine(AKA: Heroin) — Preceding unsigned comment added by 24.98.250.155 (talk) 02:16, 18 October 2011 (UTC)

I completely agree.

IV bupe is definitely 40x the strength of oral Morphine, but I doubt it is much higher than that. Yet there is no way sublingual use is quite that strong. If sublingual we're truly 40x the strength of (oral) morphine, than IV bupe would have to be over 100X the strength.

Just so we're clear, the relative BA of sublingual ranges from as low as 18%, to around 35%, giving it 1/3rd the potency, at best. If alcohol is used, the BA goes up significantly(as it increases absorption), and thus, you can get over 40% of the dose. Still, best case scenario, IV is over double the strength of the INTENDED route, and in some cases, 4-5x the strength.

Point is, this article needs clarity, as far as bupe goes. I have searched, and can't extrapolate what MOA the article refers too. SO someone, please help rectify this, to make wiki as informative and accurate a resource as possible, for the many people faced with using opiates/opioid on a daily basis.

Truly, Lorne — Preceding unsigned comment added by 76.122.100.126 (talk) 00:12, 10 April 2012 (UTC)

I just went through a similar process correcting the Buprenorphine article, as far as dosage comparisons with other opioids/opiates. It seems like a very difficult if not impossible question to answer; this is for several reasons:

* Method of administration, as mentioned above

* The question of whether the person taking it has a tolerance to opiates

* The question of number of doses per day of either substance used

But this is surely a very important article -- I'm absolutely sure many people use this or similar equivalency lists to find a dosage for their own recreational uses. Obviously, bogus info can lead to injury, while this of course isn't the purpose of this article. I don't know the answer; the most common sense approach seems that it would be to list different dosages used for different purposes: Opiate withdrawal maintenance, acute pain management, etc. -- as is listed in the overview to the Buprenorphine article.

Pfoot (talk) 21:07, 6 September 2012 (UTC)

Added Columns

I added two columns, for bioavailability and half-life. All info sourced from the drugs individual wikipedia article unless otherwise sourced. The Irish Intinian (talk) 23:06, 21 December 2011 (UTC)

Half life of fentanyl is orders of magnitude off the chart

The given half life of active metabolites of fentanyl (0.04 hours) is orders of magnitude off the chart. The real value is about 3-5 hours. Perhaps someone mixed it up with remifentanil. Surely no one injects new fentanyl every couple of minutes. — Preceding unsigned comment added by 193.175.73.206 (talk) 05:37, 7 February 2013 (UTC)

No, I believe 0.04 hours is in the correct order of magnitude for IV administration. That's my subjective experience from a week or so on IV fentanyl (self-administered button at Stanford Hospital). For a more objective half-life please see WP's Fentanyl page in the right hand column, which states 2.5 minutes. Your 3-5 hours must be for one of the patches (transdermal administration), although the (Mylan Fentanyl Transdermal System CII) patches I have come with a medication guide which lists a mean half-life of 20-27 hours. Note there are a lot of accidental overdose deaths from fentanyl and overestimating the half-life could be one cause - IMO it'd be VERY unwise to switch to fentanyl without using the dose-conversion guidelines from the Rx Med Guide for the particular patch in question.

Rad314 (talk) 21:23, 9 March 2013 (UTC)

Add entry for Pentazocine

Starting point: Pentazocine. Rad314 (talk) 21:34, 9 March 2013 (UTC)