Talk:Ranitidine

Structure

I think you might need to check the structure of this, the nitro group should not be connected to a ethylene group, it looks like its just a methyl group. Check this out: [1]

You're correct, thanks. I've amended the structure. -Techelf 09:26, 21 March 2006 (UTC)

Need to mention that it may cause false positive drug test for methamphetamine. (this unsigned comment was added on 29 June 2007 by 4.244.159.249)

Price

This has become an amazingly inexpensive drug. I recently bought a bottle of 240 generic Ranitidine tablets (75 mg) at Sam's Club for $5.88 (i.e., 2.5 cents/tablet). Is it appropriate to put something in the article about the price? NCdave 13:59, 17 September 2007 (UTC)

Shortage?

Some of the eBay auctions for Ranitidine mention "the ranitidine shortage." Is there such a thing? What is causing it? Should it be mentioned in the article? NCdave 14:01, 17 September 2007 (UTC)

Abuse and False Positives

Reference source "2" does not support the statements in the "Abuse and False Positives" section. I searched through a couple of journal databases but couldn't find any confirmatory research for this. However I found some anecdotal support for this in Introductory clinical pharmacology (Roach & Ford, 2008)(Available for viewing online at Google Books). Someone with more expertise in pharmacology might be better positioned to appraise the source and amend the article. Jdcounselling (talk) 16:35, 17 December 2008 (UTC)

Metabolism?

Can experts expand on this article to include more information on metabolism? It states that clearance mechanisms are hepatic, but can we be more specific? --1000Faces (talk) 20:37, 20 December 2009 (UTC)

Error in text?

This esentence appears in the article "The drug not only increases gastric pH, but also reduces the total output of gastric juice." I believe it should say "not only decreases gastic pH" - can some competant person please check this out and take appropriate action? <span style="font-sinaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

No, increases is correct. Bear in mind that a pH BELOW 7 indicates an acid, and the LOWER the pH the STRONGER the acid. A typical human stomach juice pH is about 2.5. I don't know how much change ranitidine usually makes but just for example's sake, it might increase it to 3 or 3.5. pH=-log10([H+]) where log10 is the base-10 logarithm and [H+] is the concentration of hydrogen ions in the solution in moles per liter. Note the negative sign in front of log10. So a pH of 2 means that there are 10^-2 (or 0.01) moles of hydrogen ions per liter of liquid. A pH of 3 would mean 10^-3 (or 0.001) moles per liter, which is 10 times weaker. Sbreheny (talk) 02:44, 14 October 2019 (UTC)

Antihistamine use and Anaphylaxis

Ranitidine is being used in emergency medicIne and in EMS for treatment of severe allergic reactions and anaphylaxis, side by side (but not replacing) H1 blockers like Benadryl. I think this should be mentioned. I have the refereces but my Wiki -fu is not yet great. I can barely sign my name. :) (Croaker260 (talk) 19:51, 24 April 2012 (UTC))

Small Error - Missing Date (Year)

There need to be a year here.

Zantac (ranitidine) 300 mg tabletsRanitidine was first prepared as AH19065 by John Bradshaw in the summer of YEAR in the War research laboratories of Allen & Hanburys Ltd, part of the Glaxo organization. 192.139.126.234 (talk) 16:02, 6 September 2013 (UTC)

User

Can this medication can cause gain weight ? — Preceding unsigned comment added by 174.65.64.95 (talk) 05:16, 12 February 2014 (UTC)

Patent enforcement

This could be an additional section if anyone has access to the printed copies of journals like Reports of Patent, Design and Trademark Cases (RPC) and Fleet Street Reports: Cases on Intellectual Property Law (FSR). An FCIPA former colleague (named by the judge in one of those law reports) resigned from Glaxo because even though he had given his written professional opinion (referred to in the judge's decision) that the UK "epimer" patent was invalid for lack of novelty, he had been ordered to attempt to enforce it.

If anyone wants to follow this up - look for John C. (or The C. Report) in the law reports. I could supply his full surname, but will not do so in a public forum. Narky Blert (talk) 00:54, 6 October 2016 (UTC)

2019 recall

Craig Hicks, Did Sandoz Canada cancel their recall? Here is an excerpt from the Health Canada press release:

One company, Sandoz Canada, is recalling its oral prescription products in Canada and other countries after testing identified levels of NDMA above what is considered acceptable if the drug were to be taken over a lifetime. Should any additional recalls be deemed necessary, Health Canada will update the table below and inform Canadians.

Sandoz Canada Ranitidine Product Recall (2019-09-17)

Sandoz did post a recall notice but the page is gone. Cache Current

Whywhenwhohow (talk) 05:01, 20 September 2019 (UTC)

according to NYT:

The Italian government said it was recalling all versions of ranitidine where the active ingredient was made by Saraca Laboratories, an Indian manufacturer, and that it was halting the use of some other versions of ranitidine while it studied the issue.

The agency, Health Canada, said Sandoz had agreed to recall its ranitidine products in that country.

https://aifa.gov.it/-/comunicazione-aifa-sui-farmaci-contenenti-ranitidina

https://www.nytimes.com/2019/09/19/health/zantac-recall.html

50.204.222.69 (talk) 16:31, 23 September 2019 (UTC)

Whywhenwhohow At the time I was following this issue, my focus was on FDA announcements and not Health Canada, so I am not sure what actions were taken regarding ranitidine in Canada. Craig Hicks (talk) 06:56, 4 February 2020 (UTC)

Is this cited correctly?

I'm finding a problem with this recent addition. The text currently reads:

In October 2019, the U.S. Food and Drug Administration (FDA) observed that a third-party laboratory was using higher temperatures in its tests to look for nitrosamine impurities. The NDMA was generated by the added heat but the higher temperatures were recommended for using a gas chromatography–mass spectrometry (GC/MS) method to test for NDMA in valsartan and angiotensin II receptor blockers (ARBs).[59]

But when I clicked footnote 59, I couldn't find anything to back this claim up at the cited source. Can someone find that claim on that source? Or was the wrong source cited? Or is this totally erroneous?

RK (talk) 18:58, 5 October 2019 (UTC)

It looks like the FDA updated the page. Here is a excerpt from a cached version

https://webcache.googleusercontent.com/search?q=cache:2VotAXMRH84J:https://www.fda.gov/drugs/drug-safety-and-availability/fda-updates-and-press-announcements-ndma-zantac-ranitidine+&cd=1&hl=en&ct=clnk&gl=us

Update [10/2/19] FDA is continuing to test ranitidine products from multiple manufacturers and is assessing the potential impact on patients who have been taking ranitidine. In addition, the agency has asked manufacturers of ranitidine to conduct their own laboratory testing to assess levels of NDMA in their ranitidine products and to send samples of ranitidine products to FDA to be tested by our scientists.

FDA observed the testing method used by a third-party laboratory uses higher temperatures. The higher temperatures generated very high levels of NDMA from ranitidine products because of the test procedure. FDA published the method for testing angiotensin II receptor blockers (ARBs) for nitrosamine impurities. That method is not suitable for testing ranitidine because heating the sample generates NDMA.

FDA recommends using an LC-HRMS testing protocol to test samples of ranitidine. FDA’s LC-HRMS testing method does not use elevated temperatures and has shown the presence of much lower levels of NDMA in ranitidine medicines than reported by the third-party laboratory. International regulators using similar LC-MS testing methods have also shown the presence of low levels of NDMA in ranitidine samples.

FDA will test ranitidine oral solution products and has begun testing samples of other H2 blockers and proton-pump inhibitors to help inform this ongoing investigation. To date, the agency’s early, limited testing has found unacceptable levels of NDMA in samples of ranitidine. The agency will provide more information as it becomes available.

Whywhenwhohow (talk) 13:45, 24 October 2019 (UTC)

References

Manufacturing/synthesis like in other drug wikis

Many other drug articles give some rudiments of synthesis. This bears on the dimethylnitrosamine recall: where in the manufacturing process would DMNA be introduced? Or does it form spontaneously on decomposition? The reference given does not mention origin, just presence. The information leads to fact that only one offshore manufacturer supplied all generic and name brand retailers. Recently, another medication (possibly the same international manufacturer) was found to contain DMNA but another 'how could it contaminate the product?' question. TaylorLeem (talk) 18:55, 21 November 2020 (UTC)

Word "is" recall vs. a claim of "safe"

Amidst ongoing robocalls attempting to find next of kin for a pharmaceutical about which, two years ago, the New York Times wrote "some experts are advising expectant mothers to use alternative forms of relief" seems to need some editing: there is a need to question restoring the word "is" before "considered generally safe in pregnancy." Nuts240 (talk) 04:20, 14 July 2022 (UTC)

@Nuts240: Please don't add medical claims that don't have sources that meet WP:MEDRS guidelines. See WP:MEDMOS and WP:NOTNEWS. --Whywhenwhohow (talk) 06:42, 15 July 2022 (UTC)

non-medical journalism

@Whywhenwhohow:(single sentence, as labeled above- comments?): While a 2005 Wiley text proclaims "considerable use in pregnancy over the last 30 years with an excellent safety ... " WebMD has recently said "Not recommended" and in 2020 The New York Times published "some experts are advising expectant mothers to use alternative forms of relief." Nuts240 (talk) 12:14, 19 July 2022 (UTC)

Cleanup flag: Hard to understand

Can this flag be removed? This section as it is now doesn't seem particularly complicated or difficult to comprehend to me. 208.68.20.28 (talk) 14:15, 25 October 2022 (UTC)

Ranitidine is unstable and decomposes to carcinogen NMDA

The CEO of Valisure admitted in a WSJ letter to the editor on 23/12/2022 that ranitidine is unstable and decomposes to NMDA. That is, NMDA concentration will increase until the parent compound is gone. The Wikipedia article claims NMDA is an impurity, but that is inaccurate - it is the 'natural' result of aging of the pure (?) parent compound. Article needs to be rewritten to remove some of the Pollyanna-ish verbiage.174.130.71.156 (talk) 02:00, 29 December 2022 (UTC)

Yup. Good source: https://www.bloomberg.com/news/features/2023-02-15/zantac-cancer-risk-data-was-kept-quiet-by-manufacturer-glaxo-for-40-years

Yet it's still available in places. There's also too much howto stuff here for a med that should never be taken. Tanishism (talk) 21:16, 20 February 2023 (UTC)

Could use some help with incorporating content from the Bloomberg article ; see https://en.wikipedia.org/wiki/Wikipedia:Media_copyright_questions#Proactive_request_for_input

--Tanishism (talk) 05:28, 24 February 2023 (UTC)

Last edit - subtitle of Bloomberg piece?

@Nthep - It's not the opening paragraph.  It appears above the byline.  . See https://en.wikipedia.org/wiki/Help_talk:Citation_Style_1/Archive_33#Subtitle%3F. You still think it shouldn't be there? Tanishism (talk) 23:25, 24 February 2023 (UTC)

Yes, it shouldn't be there. Above or below the byline it is not part of the title but the equivalent of a lead paragraph herel Nthep (talk) 07:15, 25 February 2023 (UTC)

Modification and clarification of paragraph discussion regulatory action in April 2020

I removed a paragraph that had been ripped straight from the EMA's interim report press release and inserted clumsily into the article and replaced it with something that fit in and led naturally, did not restate what had been stated in the previous paragraph, and cited the authoritative ruling's announcement, which is the same text as the interim announcement that was linked before.

I may have made some factual or semantic errors, as I do not quite understand the workings of the European Union or its regulatory structures to any degree of sophistication. Regardless, I believe this is an improvement and I welcome feedback and corrections. Dylan Lainhart (talk) 19:22, 27 March 2023 (UTC)

Not Off Market Everywhere

“As of May 2021, ranitidine has been completely withdrawn from the market.” Is this out of date? Or did my doctor and pharmacist not get the memo? Perhaps the statement should specify which market. Humphrey Tribble (talk) 02:54, 21 November 2023 (UTC)

I have now had time to check the reference. It doesn’t say “ranitidine “has been completely withdrawn from the market.”so it fails verification on that point alone. Aside from that, quick web scan shows ranitidine is still easily available.

Please use caution with phrases such as “everywhere”, “all”, or “entire”, especially if US government agencies such as the FDA are involved. The US is only a small part if the world. Humphrey Tribble (talk) 01:06, 26 November 2023 (UTC)