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At the present time (see sig), the information on toxicity seems rather inconsistant. We have the following statements:

• Intravenous LD50 > 32 g
• Oral LD50 is 13-19 g
• Oral LD50 is 150-200 mg/kg, or 7.5-10 g for a 50-kg person

The big question here is, how can intravenous LD50 be greater than oral LD50? Vectro 04:31, 8 May 2006 (UTC)

According to some sources, Espresso is the form of coffee with the least amount of caffeine, the explanation being that when making an Espresso, the water comes into contact with the coffee powder only a very short time.

For example, The Economist (admittedly no scientific publication) writes:

(...) it [Espresso] contains less caffeine than almost any other form of prepared coffee.

See Espresso coffee (The Economist)

• I agree with the anon above. The National Geographic [1] article on caffeine stated that espresso has around 40mg per ounce, not 100mg. I am going off of memory as I do not have a subscription, but it seems what whomever posted the espresso content was making things up. Espresso is a darker bean, roasted longer (which reduced caffeine content) and it contains less water, which reduces caffeine content due to the fact that it is barely water soluble (which is why we need to heat our water for coffee and tea).

• Also, I am skeptical of most of these caffeine content figures, there are no sources cited.

Reid 20:34, 7 February 2006 (UTC)

The article cites robusta. This variety has more caffeine than the most common variety used for taste: arabica. Thus, the amount given might be OK. Jclerman 22:00, 7 February 2006 (UTC)

Robusta is not by any means used in all types of espresso, and then only as a minority portion of a blend (mainly as a crema-enhancer). Arabica remains by far the main element; most of the blends I've seen appear to have no better than perhaps a 1/6 ratio of Robusta to Arabica.

100 mg per shot is a gross exaggeration. There are plenty of reliable sources out there to verify the 40mg per ounce fact. —The preceding unsigned comment was added by Melllvar ( talk • contribs) 2006-03-21 11:48:10 (UTC)

Is there a hydrogen atom missing in the diagram? I only count nine but the chemical formula says ten. It appears to me that it should bond to the carbon on the left hand side that only shows three bonds. 20:25, 14 Nov 2004 (UTC)

Isn't there some kind of organic chem convention where you can omit obvious hydrogens? Pakaran (ark a pan) 20:31, 14 Nov 2004 (UTC)

Thanks for clearing that up. I didn't know for sure. I would show the hydrogen for clarity, but I'm not a chemist, so it is probably alright the way it is. Thanks again. 21:03, 14 Nov 2004 (UTC)

Yes, there is one hydrogen atom present but not shown at the tip of the five-membered ring. This is omitted to simplifiy the drawing of the structure. Since each carbon has four bonds, any carbon atom that shows less than four bonds is bonded to enough hydrogen atoms so it will be using four bonds. 29 Jan 2006

I don't know where this fact belongs, and I don't have a reliable reference, but as I understand it, in Canada there are restrictions on what drinks can contain caffeine - you can't add it to clear pops or juices, only colas. Canadian Mountain Dew has no caffeine. This is being circumvented by adding guarana... -- Andrew 15:41, Apr 24, 2005 (UTC)

Of course, Guarana actually CONTAINS caffeine itself, but via loopholes in both Canada and the U.S., it doesn't need to be labeled as caffeine per se because it's within the guarana, a natural substance, as opposed to being in the form of pure caffeine powder, which is what's normally added to soft drinks. So guarana Mountain Dew will actually have caffeine, but consumers won't be told this.

• In fact, Mountain Dew Energy, sold in Canada, contains caffeine as a medical ingrediant, listed as such - the regulartions about this sort of thing are a little looser than they used to be. WilyD 22:37, 1 March 2006 (UTC)

Guarana is a bright red berry similar in size and shape to a cranberry, the outside fruit of the berry contains little if any caffeine, this is used in carbonated drinks like Anarcticas Guarana and Coca-cola's Kuat. The seed is where the main caffeine concentration is found, it is sold in a highly potent powder form.

The article mentions, However, this is impossible; caffeine is an achiral molecule with no chiral centers, and therefore has no stereoisomers.. If I understand the phrasing correctly that caffeine is achiral because it has no chiral centers, then that's contradicted by the article on chirality which states, It is also possible for a molecule to be chiral without any specific chiral centers in the molecule. The articles on axial_chirality and planar_chirality support that notion, as well. Can someone verify the article's assertion from scientific sources like a peer-reviewed journal article or review on caffeine? - Gyan 02:36:10, 2005-09-04 (UTC)

Take a look at the caffeine molecule. It's obvious that there are no chiral centers - all tetravalent atoms (i.e. carbon atoms) have at least one double bond or two identical neighbors. There are no chiral axes either: The only potential chiral axis is between the two central carbon atoms which share a double bond. The ligands of those carbon atoms, however, cannot be inverted without altering the molecule's connectivity. As for potential planar chirality - the caffeine molecule is pretty much planar, so that makes no sense at all. If the achirality of this simple molecule is still disputed, however, I challenge people to come up with a depiction of an actual stereoisomer (e.g. "mateine" or "guaranine"), then we can discuss whether that's actually structurally identical and exhibits a different configuration -- there's simply a limit on how much the burden of proof should be allowed to shift in this debate. Aragorn2 20:14, 18 December 2005 (UTC)

You have to look at the nitrogen atoms in the molecule, since they can be chiral as well. It looks to me like the nitrogens are chiral centers.

Nitrogen can be a stereocenter if it's locked in one tetrahedral geometry (3 single bonds + 1 lone pair; a high energy barrier to inversion). However, that is not the case in caffeine. The lone pair on each of the nitrogen that is written with three single bonds is involved in resonance with the adjacent carbonyl. This makes the bond between N and C somewhat like a double bond: the nitrogen is sp² hybridized, and is therefore planar not stereogenic. Even in molecules where the nitrogen lone pair is not involved in resonance, the barrier to inversion of the tetrahedron is very low, so that one has a rapidly interconverting mixture and cannot handle each enantiomer separately. Therefore, although there is technically a stereocenter at N, one doesn't usually consider such molecules as "chiral" in a practical sense for ordinary organic chemistry. DMacks 07:51, 24 March 2006 (UTC)

1. Melting point: 238 °C
2. Boiling point: 178 °C (sublimes)

Isnt it meant to be the other way round ? When i did Chem things normally melted and then boiled? -- 2mcm ^Gespräch 20:10, 26 October 2005 (UTC)

Actually, you got it right on the head. Under normal conditions, most things do melt before they boil. But caffeine, under most conditions, sublimes- it goes directly from a solid to a gas without any liquid phase. If you worked with iodine, the same thing probably happened. Dry ice is another example- it's carbon dioxide that goes directly from a solid to a gas without an intermediate stage. Even water can be coaxed into doing this- in fact, most any substance can. -- 2tothe4 23:22, 27 October 2005 (UTC)

But then how can the melting point be higher than the sublimation point? Surely substances that go straight from solid to gas do not have a melting point or have a melting point equal to their boiling point right? -- 81.106.138.21 15:16, 22 March 2006 (UTC)

Boiling/sublimation point is highly dependent on pressure, whereas melting point is much less sensitive to pressure. If you were to operate at a pressure where sublimation does not occur, you would see an ordinary solid-liquid transition. That is, as you raise the pressure, the sublimation point goes up (as usual: higher P leads to higher bp). Eventually, the sublimation point will be higher than the mp: you'll have a span of temperatures "above mp but below bp"--a distinct liquid phase. Visit Phase diagram for more info. DMacks 20:02, 22 March 2006 (UTC)

How is caffeine used as a pain relief enhancer in medicines like Exedrine? 153.104.16.114 01:50, 11 November 2005 (UTC)

It might be related to the action of caffeine on the adenosine receptors which mediate(s) antinociception, thus helping with the analgesia of muscle and bone. Hence, it might work alone, without aspirin or acetaminophen (paracetamol) in the formulation. Don't consider this medical advice, just my unproven hypothesis. Jclerman 03:10, 11 November 2005 (UTC)

I have read that caffeine has no documented enhancing effects when used with pain relievers. However, this article states ""There is no evidence that caffeine relieves pain, but it can enhance the effects of aspirin, possibly by lifting a person's mood," says Michael Weintraub, M.D., director of FDA's Office of OTC Drug Evaluation." PrometheusX303 13:39, 15 January 2006 (UTC)

It is also useful to consider that caffeine withdrawl is a very common cause of headaches, so to add it to pain relief pills is a fair method of covering bases. Of course, that's speculation, and is not appropriate for the article proper. – Clockwork Soul 16:22, 16 January 2006 (UTC)

As an organic chemistry student, I'm finding the drug page on caffeine to be inadequate. Is someone willing to write an organic compound article, following that format (see dichloromethane)? I don't do much of this sort of thing, but if someone were to write Caffeine_(chemistry) or whatever the standard would be, I think it would be helpful. -- horsedreamer 18:36, 16 November 2005 (UTC)

Well, with your credentials you should certainly be able to make a start! JFW |  T@lk 20:46, 16 November 2005 (UTC)

Check the page how: how's that look? – Clockwork Soul 19:30, 2 January 2006 (UTC)

I'm doing a biology project on drugged spiders' web patterns. This article has only one sentence about it and actually the resources are limited. I was just asking if you could add some more about that, or advice me a source, etc. Thanks for your time. -- Quinlan Vos 19:58, 27 November 2005 (UTC)

Will this message ever get attention? I really need some info from chem students. Thank you for your time again. -- Quinlan Vos 01:46, 18 January 2006 (UTC)

Heyy.. Dude, spiders are like really far out. I mean, like drugs are too.. but spiders are just whoa. you know? yeaah.

• Though this is a talk page, try and stay on subject please... The PA 17:58, 27 January 2006 (UTC)

It seems to have an anti-caffeine agenda to me. Yes, technically it is a neutral fact, but IMO it is obviously meant to imply that caffeine has analogous adverse effects on the human mind. For this, it is actually a very weak argument, because a spiders nervous system is clearly very different from a humans (and they were probably given extremely high doses anyway). Yet, the picture seem quite convincing at first glance and some casual readers will probably consider it good "evidence" for the above-mentioned conclusion (people like analogies).

Thus, I find the picture highly misleading and vote for its removal (or maybe move it to a page about spiders or differences of drug effects between species, where it would be more on-topic than here). If you want to argue that caffeine has negative effects on human cognition, fine, but please do so explicitly and not in such an unfair way.

Sorry for the rant, maybe I'm overreacting. I guess that I'm just a little tired of this kind of "reasoning".

Comment: I agree that the picture should in no way be used as evidence for the argument that caffeine is highly dangerous and/or destructive. However, I think it is a rather interesting bit of information and should remain. I've seen two other similar pictures, where the spiders were on LSD and marijuana (not both at the same time). The LSD web was even more geometrically perfect than the average spider web, and the marijuana web was loosely constructed and unfinished. It would be foolish to speculate from these pictures that caffeine is destructive to thought and organizational thinking or that LSD enhances performance. Here is one of many links that has pictures of various drug-induced webs: http://www.trinity.edu/jdunn/spiderdrugs.htm

There is no claim or insinuation that caffeine is highly dangerous, and considering that plant caffeine serves as an insect deterrant, the reason for its effect on arthropods is clear. The article makes no such claims about humans, however. – Clockwork Soul 15:12, 26 January 2006 (UTC)

There is one point about the spider drug testing. Caffiene is actually more toxic than many of the other drugs tested (such as marijuana) in terms of the amount in mg per kg of bodyweight that needs to be consumed. If we consider that the spiders used probably only weighed about 0.1g at best, then even the very small amounts of caffiene given to them are bound to be more toxic. Mostly Zen 17:15, 10 May 2006 (UTC)

PS: 1% caffiene solution is used as an 'environmentally friendly' slug repelant. It kills them good.

This is in response to this edit, with the comment "No caffeine, http://www.mrkland.com/fun/xocoatl/caffeine.htm". Your post prompted me to do a detailed search on the claim (I want everything to be accurate as possible), and I found the following results:

• The cited web page has a "science page", which cites "Biochemist, Apr/May 1993, p 15. copyright of Royal Society of Chemistry website 2000" as its source. However, no such journal as "Biochemist" exists.
• I found a few journals with similar names, though: Biochemistry, Bioconjugate Chemistry, and Biomacromolecules. Searching the entire year of 1993 turns up two articles that mentioned caffeine in the article body, and none that mentioned both caffeine and chocolate.
• A quick PubMed search however, finds quite a number of articles that mention finding caffeine in both cocao and chocolate in the small quantities mentioned in the caffeine article. [2] [3] [4] [5]
• Other sources confim this, including the International Cocoa Organization and the International Food Information Council.

Clockwork Soul 23:14, 3 January 2006 (UTC)

The article currently contains the following sentence:

"In addition, Arabica coffee, which is widely regarded as the highest quality of commercially produced coffee, contains less caffeine content than the Robusta variety, which is normally used in instant coffee or is combined with arabica to produce a flavorful yet highly energizing coffee drink"

It seems to claim special "energizing" qualities for a drink made from both arabica and robusta. This sounds rather like quack science. I can think of two possibilities:

1) the article previously contained a brand name of some energy drink containing both types of coffee bean, and that the brand name has been removed to leave a rather misleading sentence.

or

2) someone genuinely believes that a mixture of the two coffees has this special property... for which there seems to be no evidence whatsoever.

Either way, I think the phrase "yet highly energizing" has got to go.

I'll wait for a second opinion before going ahead, but if anyone else agrees please go ahead and make the change.

• I'm with you. At the very least, it's POV. I'm removing it now. – Clockwork Soul 22:25, 21 January 2006 (UTC)

I don't think it's meant to claim that the combination has a special property; rather, it is simply stating, in a rather strange way, that combining the two beans combines the properties of both. ie, the flavour of arabica and the high caffeine of robusta. More often I think the two are combined for the cheapness and high yield of the robusta, rather than the caffeine. 57.66.51.165 14:28, 1 March 2006 (UTC)

Comment about a paragraph that perhaps needs correction: It is my understanding that one of the reasons that determines which source of caffeine is used (natural -extracted- or artificial -synthesized-) is the respective country regulations, i.e., whether they require to use only natural products in the drinks. Some manufacturers of soft drinks used to obtain "forensic" carbon isotope analysis on batches of caffeine in order to decide whether to use them in their drinks. Jclerman 17:22, 28 January 2006 (UTC)

• If you can find a source for that, it would be a welcome addition/correction to the article. – Clockwork Soul 16:13, 29 January 2006 (UTC)
  • I'll try to find something. My unpublished source is my witnesing it while I did research in a radiocarbon dating lab in Europe. Jclerman 22:06, 9 February 2006 (UTC)
  • There should be a paper somewhere. I'll do a bit of searching, too. – Clockwork Soul 01:14, 10 February 2006 (UTC)

Can someone go over to cocoa and write about its chemical composition? it seems the caffeine article has more information on it that its own article. -- Fs 11:31, 17 March 2006 (UTC)

Report by China Central TV

It seemed that in some places in Shanxi, China, people are abusing caffeine in a way not dissimliar to heroin; they even "chase the dragon" and there are illegal labs synthesizing caffeine from theophylline since the former is a controled substance in China yet the latter isn't.

Should it be added to this article? —The preceding unsigned comment was added by Samuel Curtis ( talk • contribs) .

• The article is unavailable now, but I'm personally skeptical of articles posted on any tightly-controlled state-operated media, especially when it has do do with a substance that is banned. This smells of propaganda to me, and I would prefer that we wait for a less potentially biased source. – Clockwork Soul 20:51, 19 March 2006 (UTC)

Guaranine is not any more the mixture that it was for von Martius. For the ChemId Plus, PubChem, and ACS (CAS numbers) databases it is a synonym of caffeine. Same structural formula. When searching in ChemId Plus, (either Lite or Advanced) look for all names and synonyms. Enter guaranine in the search boxes of the databases linked below and read the findings, the formulas, the code numbers, the references, etc. Similarly, you'll also find that a synonym of caffeine is mateine, which still is believed by many to be different from caffeine. There is no doubt. Since the structural formulas are identical the pure substances are identical. In the respective plants they might bind with different compounds, that's why coffee and tea and mate and guarana drinks are different. But the pure crystaline substances are identical. For an ethnobotanical overview based on von Martius findings and their sequel see the Raintree Tropical Plant Dabase: Guaraná. Another ethnobotanical database is "Dr. Duke's".

The links below take you to the URLs where to initiate searches. Just enter guaranine or any other drug name in the search boxes.

• PubChem

• ChemIDplus Lite

• ChemIDplus Advanced

• TOXNET

Jclerman 00:58, 24 March 2006 (UTC)

Is guaranine actually caffenine? There are some that claim it is actually tetramethylxanthine (there is no stub for this chemical). I could not find any credible sources to back up this claim, although it is listed on PubChem with two isomers. -- 203.59.142.36 02:36, 6 April 2006 (UTC)

• Tetramethylxanthine is methylated caffeine, but guaranine is most definitely caffeine. – Clockwork Soul 03:30, 6 April 2006 (UTC)

The description on how caffeine works becomes misleading when it states "The result is an increase in the levels of epinephrine or adrenaline and norepinephrine released via the hypothalamic-pituitary-adrenal axis[4]". As far as I understand it, adrenaline is released from the adrenal medulla under stimulation by the sympathetic nervous system. The hypothalamic-pituitary-adrenal axis is involved in the release of corticosteroid hormones such as cortisol, NOT adrenaline. ( Castewart 10:17, 14 April 2006 (UTC))

Just reviewed this nomination. This is a very nice article and it seems pretty comprehensive. The popular culture aspects are covered as well as the metabolism and science. I think my main criticism would be that the refs really need cleaning up and converting to inline refs. Walkerma 04:06, 19 April 2006 (UTC)

Citations were a mixture of inline links ([http://foo]) and footnote references (<ref>; see WP:FN). I just converted to all footnote refs because it seems to be the Funky New Method in wikipedia. However, now I'm not sure the change is desired: most were of the inline format, and formatting is often just a matter of personal preference (so stick with the initial choice unless compelling reason or consensus). So anyone feel free to revert or to complain and I'll revert and fix the stragglers to inlines. DMacks 18:30, 24 May 2006 (UTC)

I noticed methyltheobromine listed as an alternate name. This struck me as an odd name, as the molecule obviously lacks a Bromine. Is this right? Tyro 09:44, 2 June 2006 (UTC)

Yup. Check the second sentence of theobromine to learn the origin of its name. DMacks 15:42, 2 June 2006 (UTC)

Interesting, thanks! Tyro 04:34, 7 June 2006 (UTC)

What is the purpose/properties of putting/allowing caffeine in soft drinks and other beverages (assuming we're not talking about an Energy Drink or something else promoted as a stimulant)? Does decaffeined soda taste different than its counterpart? What is the justification for not having more decaffeinated beverages?

a reason may be flavor. caffeine is very bitter - if you would produce coca-cola without caffeine, it would taste totally different. (unless you would find an alternative bitter flavoring)

also i think many drinks are consumed because of their caffeine content. cola is often consumed because of the effects of caffeine in it. consumers probably wish to have a caffeinated drink that has less caffeine then a energy drink like red bull etc.

81.221.211.102 23:51, 2 July 2006 (UTC)

-> Soft drink companies claim the taste of caffeine is the reason they have it in there, however tests show that only a small percentage of people can consciously tell the difference if they try. So what that guy above me said is completely wrong. The conclusion I read for this was that "soft drink companies know consumers are addicted to the caffeine in it." I would like this to be true... because that would mean a small bit of caffeine can have a substantial lift that we crave. However, if even a small percentage of people are clued in that caffeine is in soft drinks, then they might be more likely to buy them... so who knows?

...which are incomprehensible to those used to metric units especially when they're used with SI derivative units. I'd propose some unit cleaning & internationalizing for the article, eg. I have no idea what the following means: ~2 shots of espresso from robusta beans (2 floz) (what is floz? what is a shot in this context?)....Remember that the readers are a global crowd.

"Floz " is a typo for "fl oz," or "fluid ounce." A British fluid ounce is 28.413 ml (found on http://convert.french-property.co.uk/); American fluid ounces are very slightly different, but I think they are also approximately 28.4 ml. 140.247.131.116 20:31, 4 January 2006 (UTC)

The article also doesn't even begin to cover the positive effects of caffeine. Infact the article is heavily biased towards caffeine is teh evil substance while it has many positive effects to the human body.

Here are few example links for the positive effects: http://www.newscientist.com/article.ns?id=dn3619 http://www.medicalpost.com/mpcontent/article.jsp?content=/content/EXTRACT/RAWART/3623/23A.html http://www.cosic.org/coffee-and-health/alzheimers-disease http://www.abc.net.au/rn/talks/8.30/helthrpt/stories/s30640.htm http://www.indianpediatrics.net/dec-99/99-dec-20.htm http://www.faqs.org/faqs/caffeine-faq/

-> yeah, some guy has deleted some of what was there and written a full section on tolerance... but he makes it sound like you'd be stupid to drink coffee to begin with (for anything more than its taste), because the tolerance has a perfect rubber band effect. Some people just can't get this "conservation of energy" out of their heads, especially for an everyday substance like coffee (and who's willing to bet these are the very same people who megadose on actually bad and useless things nootropics and brain pills?). Sure, maybe if we all ate nothing but raw organic foods and lived peaceful lives, sleeping for 12 hours a night, under no stress and only exercise for work, the maybe refraining from coffee might add another week or two to our 90 years existance. But the modern world demands coffee and to go without it and still be under all that is the worst thing you could do.

I don't think the article is anti-coffee; I was actually surprised because I'd read a previous version that was. I hope any positive effects of caffeine have ended up - or will end up - in the article. But it's important to differentiate between the reported or purported health benefits of caffeine and those of coffee and tea. Anchoress 20:45, 20 August 2006 (UTC)

What is USP, mentioned in the image text? United States Pharmacopoeia?

yes probably is - it might be a good idea to change this to "pure caffeine" because that is probably what it its. (this would be especially good for readers outside of the US) 81.221.211.102 23:53, 2 July 2006 (UTC)

What does "pure" mean? DMacks 02:54, 6 July 2006 (UTC)

"USP" indeed is an abbreviation for United States Pharmacopoeia (and is the only relevant-sounding meaning in the USP page). In the context of the image text, it is an indicator of the grade (purity and types/amounts of various impurities) of the material. To quote the Pharmacopoeia page, "the initials USP are affixed to materials' names to indicate that they conform to the specifications in the USP". DMacks 03:00, 6 July 2006 (UTC)

I don't have a chance to look over it in detail at the moment, but some of the grammer seems awkward if not wrong.

While relatively safe for humans, caffeine is considerably more toxic to some other animals such as dogs, horses and parrots due to a much poorer ability to metabolize this compound. Caffeine has a much more significant effect on spiders, for example, than most other drugs do.

While I am not compleatly sure if that is wrong, it just sounds akward. I was thinking of changing it to

While relatively safe for humans, caffeine is considerably more toxic to some other animals such as dogs, horses and parrots due to a lesser ability to metabolize this compound. Caffeine has a greater effect on spiders, for example, than most other drugs do.

I'll look over this article when I have time tonight to seem if theres any other examples.

CBush98 20:41, 11 July 2006 (UTC)

Perhaps you mean spelling, semantics, syntax, and/or grammar? -- 69.9.27.14 20:47, 11 July 2006 (UTC)

From ChemId @ the NLM full database. You can find the reference in a section of the article guarana with direccions of how to use it.

The synonyms are: mateina (original Spanish) - mateine (English translation, as Cafeina-Caffeine, Purina-Purine, Teina-Teine, etc). Since the putative substance was first "described" by Spanish speakers, ChemId uses "mateina", but there is a huge amount of references centered on whether mateine is or is not caffeine. All English references spell it "mateine". See, among others [6]:

Name of Substance

1H-Purine-2,6-dione, 3,7-dihydro-1,3,7-trimethyl-
3,7-Dihydro-1,3,7-trimethyl-1H-purine-2,6-dione
Caffeine
Caffeine [BAN:JAN]

Synonyms

1,3,7-Trimethyl-2,6-dioxopurine
1,3,7-Trimethylxanthine
1H-Purine-2,6-dione, 3,7-dihydro-1,3,7-trimethyl-
3,7-Dihydro-1,3,7-trimethyl-1H-purine-2,6-dione
5-26-13-00558 (Beilstein Handbook Reference)
AI3-20154
Alert-pep
Anhydrous caffeine
BRN 0017705
CCRIS 1314
Cafamil
Cafecon
Cafeina
Caffedrine
Caffein
Caffeina [Italian]
Caffeine
Caffeine (natural)
Caffeine, anhydrous
Caffeine, synthetic
Caffine
Cafipel
Coffein [German]
Coffeine
Coffeinum
Dexitac
EINECS 200-362-1
Eldiatric C
FEMA No. 2224
Guaranine
HSDB 36
Kofein [Czech]
Koffein
Koffein [German]
Mateina
Methyltheobromide
Methyltheobromine
Methylxanthine theophylline
NCI-C02733
NO-Doz
NSC 5036
Nix Nap
Nodaca
Organex
Quick-Pep
Refresh'N
Stim
Thein
Theine
Theobromine, 1-methyl-
Theophylline, 7-methyl
Tirend
Vivarin
Xanthine, 1,3,7-trimethyl

Systematic Name

1H-Purine-2,6-dione, 3,7-dihydro-1,3,7-trimethyl-
Caffeine

Superlist Name

Caffeine

Jclerman, can you find a reference that uses the English translation? I can find no such reference in any of the usual chem sources PubMed doesn't even list a single instance of either meteine or mateina (go figure!), and all Google turns up is a MiracleBurn advertisement. – Clockwork Soul 15:34, 16 August 2006 (UTC)

Wrong Google. Use Google Scholar [7]. Jclerman 15:43, 16 August 2006 (UTC)

Google scholar returns only 4 English references, still mostly advertisements. I'll still accept the translation, of course. – Clockwork Soul 15:44, 16 August 2006 (UTC)

You are correct. See the one reference that seems to be OK [8]. I've been fighting the "advertisers" of mateine as a diff subst from caffeine since 10 yrs ago. However, there is somewhere a reference, in Spanish if I remember well, claiming that there is a species of I. paraguayensis that contains less or none (?) of the stimulant.

Jclerman 15:54, 16 August 2006 (UTC)

Here are two less scholarly references than the last one referenced above. The two new ones are: [9] and [10].

• You can always rely on Erowid. I've found more excellently references material there than nearly anywhere else. – Clockwork Soul 17:59, 16 August 2006 (UTC)

I re-did the auto review incase anything has changed. Strike out the sections as they are verified or finished. The following suggestions were generated by a semi-automatic javascript program, and may or may not be accurate for the article in question.

• Per WP:CONTEXT and WP:MOSDATE, months and days of the week generally should not be linked. Years, decades, and centuries can be linked if they provide context for the article. All of these come from the cite templates.
• Per WP:MOS, avoid using words/phrases that indicate time periods relative to the current day. For example, recently might be terms that should be replaced with specific dates/times. ^[1]
• Per WP:MOSNUM, there should be a non-breaking space -   between a number and the unit of measurement. For example, instead of 18mm, use 18 mm, which when you are editing the page, should look like: 18&nbsp;mm. ^[2]
• Per WP:MOSNUM, when doing conversions, please use standard abbreviations: for example, miles -> mi, kilometers squared -> km², and pounds -> lb.
• Per WP:MOSNUM, please spell out source units of measurements in text; for example, "the Moon is 380,000 kilometres (240,000 mi) from Earth. ^[3]
• Per WP:CONTEXT and WP:BTW, years with full dates should be linked; for example, link January 15, 2006, but do not link January 2006. ^[4] All of these come from the cite templates.
• Per WP:MOS#Headings, headings generally should not repeat the title of the article. For example, if the article was Ferdinand Magellan, instead of using the heading ==Magellan's journey==, use ==Journey==.
• Please alphabetize the interlanguage links. ^[5]
• There are a few occurrences of weasel words in this article- please observe WP:AWT. Certain phrases should specify exactly who supports, considers, believes, etc., such a view. For example,
  • apparently
  • might be weasel words, and should be provided with proper citations (if they already do, or are not weasel terms, please strike this comment). ^[6]
• Watch for redundancies that make the article too wordy instead of being crisp and concise. (You may wish to try Tony1's redundancy exercises.)
  • Vague terms of size often are unnecessary and redundant - “some”, “a variety/number/majority of”, “several”, “a few”, “many”, “any”, and “all”. For example, “All pigs are pink, so we thought of a number of ways to turn them green.”
• As done in WP:FOOTNOTE, footnotes usually are located right after a punctuation mark (as recommended by the CMS, but not mandatory), such that there is no space inbetween. For example, the sun is larger than the moon [2]. is usually written as the sun is larger than the moon.[2]
• Please ensure that the article has gone through a thorough copyediting so that the it exemplifies some of Wikipedia's best work. See also User:Tony1/How to satisfy Criterion 2a. ^[7]