Talk:Quinine

vs quinidine

There is a "do not confuse" flag in both quinine and quinidine, but they appear (in the chemical formula and skeletal diagram, as well as the listed characteistics like molecular weight) to be identical. Are they merely two different medical uses of the same compound, or are they chemically different in some (unspecified in the article or data page) way? Riventree (talk) 12:25, 10 April 2017 (UTC)

Very similar they are.[1] They are isomers but not enantiomers. Doc James (talk · contribs · email) 18:12, 10 April 2017 (UTC)

The skeletal diagrams are different. If you look at the wedge-shaped connectors for each of -OH and -H in the middle of the molecule, you will see that in quinine they are solid and in quinidine the same two are dashed. That is not just as style thing - solid wedges means the bond points up out of the plane of the page, and the dashed wedge means the bond points down. See [[2]]. Those differences give the molecules different activities Jytdog (talk) 18:33, 10 April 2017 (UTC)

Contraindications

Under the "Contraindications" heading, the second to last sentence says "In people with atrial fibrillation, conduction defects, or heart block, quinine can cause heart arrhythmias, and should be avoided.[30]". The reference leads one to a study titled (which can bee seen in the references section of the article) "Off-label use of sildenafil in valvular heart disease should be avoided". So, the reference providing evidence that quinine "can cause heart arrhythmias, and should be avoided" actually refers to sildenafil. I'm no medical expert, but the reference should refer to the drug in question, quinine, and not another (sildenafil). — Preceding unsigned comment added by 73.42.197.25 (talk) 06:03, 29 May 2020 (UTC)

Traditional Use

Under History, there was a statement that: Quinine was used ... to halt shivering "due to low temperatures." This sounds rather stupid to me... shivering is feared when it is due to fever, not just "due to low temperatures" where intuitively it could be dangerous to suppress it. So I searched the citation given (which was interesting: https://books.google.com/books?id=ATQbAAAAYAAJ&pg=PA302#v=onepage&q&f=false), but I found no references at all to "shivering" or anything about low temperatures... I think some contributor may have just made this up naively thinking it was a "logical" explanation. Anyhow, I removed "due to low temperatures" unless it can be supported with a direct quote. It would still be nice to make the entire part about traditional use a bit more precise with citations pointing to the **exact** passages that support each claim. DKEdwards (talk) 19:23, 4 October 2020 (UTC)

World War II

In the article, it is stated "Tens of thousands of US troops in Africa and the South Pacific died of malaria due to the lack of quinine." While I don't have access to the book, I am unable to find any numbers backing up this fact and the number itself seems quite implausible. From https://history.stackexchange.com/questions/58525/what-was-the-estimated-malaria-death-toll-for-us-forces-during-world-war-ii , the fatality number looks closer to 100, than "tens of thousands", which would make malaria one of the leading causes of death in WWII. 2601:645:8200:61E0:31FF:79D8:983D:A4EC (talk)

Error in chemical structure of secologanin

The diagram of the biosynthesis of quinine has an incorrect structure of secologanin. The tetrahydropyran ring (six membered ring with five carbons and one oxygen), has a (correct) pendant vinyl group [pyran]-CH=CH2 and an incorrect pendant allyl group [pyran]-CH2-CH=CH2. The allyl group should actually be an acetaldehyde group, [pyran]-CH2-CH=O. I.e., change the terminal =CH2 group to an =O atom. AdderUser (talk) 06:22, 12 December 2021 (UTC)