Talk:Diphenhydramine

Receptor Binding

The information regarding receptor binding of diphenhydramine is insufficient. This is a very dirty ligand, which affects the histamine, acetylcholine, dopamine, serotonin, and other neurotransmitter systems. The article does not present sufficient information about this and makes it seem as if the substance is primarily and h1-blocker. —Preceding unsigned comment added by 24.126.151.171 (talk) 13:36, 20 February 2008 (UTC)

Conflicting information

There is conflicting information: Akathisia says it is a side effect of diphenhydramine (Benadryl), while this article says Benadryl 'prevents' akathisia. Which is correct? --zandperl 03:53, 4 May 2006 (UTC)

It can cause either or both. Like most drugs, side effects vary from one individual to the next. 12.33.211.29 20:58, 13 July 2006 (UTC)

Similarly, this article says it may cause nausea but it is listed as an antiemetic. 128.119.174.227 18:38, 2 September 2006 (UTC)

Speaking as an occasional recreational user of DPH, the nausea is more likely to be caused by shifting and surreal visual shifts, similar to motion sickness, rather than the pharmacological effects of the drug. Babelinfocalypse 13:41, 4 September 2007 (UTC) --babelinfocalypse

There doesn't seem to be much consensus about the half-life of diphenhydramine. The National Highway Traffic and Safety Administration lists the half-life as 8.5 plus or minus 3.2 hours, and rx-list.com says it's effects are felt for 4-6 hours (is that supposed to be one half-life?). --Wallabyman 05:07, 20 February 2007 (UTC)

Also, could someone put the peak plasma concentration somewhere in the article? I think a new section on pharmacology would be nice to start. I've seen 2-3 hours listed as the peak plasma concentration (again, National Highway Traffic and Safety Administration). Thanks! --Wallabyman 05:07, 20 February 2007 (UTC)

"Abuse" or "Recreational Use"

I have changed "Abuse" to "Recreational Use", because "Abuse" implies that it is wrong or immoral, and certainly is a POV. It is instead recreational to eliminate POV. If anyone has a problem with this please let me know. Ihatecrayons 14:35, 21 July 2006 (UTC)

I agree with you on that change. Eventhough, IMHO, diphenhydramine is a really shitty (and damn dangerous too!) drug to try and trip with, calling it "Abuse" is a POV. I will change the dimenhydrinate article too to reflect this. --Seven of Nine 16:36, 21 July 2006 (UTC)

That is very true, that it is a very shitty and dangerous drug for tripping with. But, some people choose to, so we have to remain unbiased. Thanks for fixing things. :D Ihatecrayons 12:11, 23 July 2006 (UTC)

I disagree: abuse is when you deliberately exceed the recommended dose. There's nothing biased about that. And does the external link to people's experiences count as a reliable source? I'm uneasy about it because it tends to encourage the abuse ie. people see what doses are needed over certain time periods to recreate those experiences. Although if the experiences were recounted in a clinical setting, for the purpose of medical inquiry, that would seem ok. In the end, WP isn't censored.--80.6.163.58 20:25, 11 April 2007 (UTC)--Shtove 20:38, 11 April 2007 (UTC)

That's the biggest problem with the term 'drug abuse', it is defined differently by different parties. I think it is generally understood to carry negative connotations though. The terms "non-theraputic" or "non-medical" could be used in place of "recreational", although I have no particular problem with the term "recreational" personally.

I agree that the Erowid link you alluded to is not suitable as a source, but as you said it's listed under the external links section and not the references. As an external link I don't see a problem with it. The phrase "usually between 100mg and 450mg" is unsourced and I personally don't think it belongs in the article. I've added a {fact} tag there and I'll take out the phrase in a few days if nobody objects. The rest of the section looks encyclopedic enough to me although it's unsourced like much of the rest of the article.--Eloil 21:31, 17 April 2007 (UTC)

Keep in mind some could be self medicating as an attempt to stay unprescribed zombies. If other forms of self med's were legal chemical abuse would not be needed. What are the long term side effects to the liver and brain? This could add to the "abuse" debate.

I say stick with recreational, abuse is a pov word when used in context to drugs. and dosage for 'high' varies as with all drugs, but Erowid is fairly accurate

I know that the American Red Cross considers intentional use for reasons outside of labeling abuse, but I do agree that there is a stigma in western culture around the word abuse. I suggest that "recreational" use be kept for the headline, but perhaps a reference to abuse could be made within the text? Also the dosage threshold between off-label use and abuse needs to determined since this drug could be used for depression which is certainly not a "recreational" use - though these levels may overlap somewhat. Datapharmer 01:54, 25 August 2007 (UTC)

Is Recreational Abuse a possibility? Whilst Abuse on its own is evidently POV, and recreational could be construed as a positive endorsement, is a compromise a possibility? As an occasional abuser (and I use that term with full connotational force) I do not wish unprepared individuals to experience this drug. The last thing I'd want is someone experiencing something which they would not enjoy. 13:39, 4 September 2007 (UTC) —Preceding unsigned comment added by Babelinfocalypse (talk • contribs)

The "Recreational use" section is messy, lacks citations, and is of generally poor quality. Erowid is not a suitable reference. Random unsubstantiated claims, such as "Diphenhydramine is a component of recreational heroin", do not belong on Wikipedia. (As for "recreational heroin"... what makes that any different from "normal" or "medical" heroin? If you mean to say "impure heroin", then say so. "Recreational heroin" is just a nonsense term.) I'm sure that people do in fact use diphenhydramine recreationally, but I think the information provided should point out dangers rather than explicitly telling readers how to use it recreationally. On this note, I'm removing the part about dosage and the reference to Erowid. To be quite honest, using this drug recreationally is utterly idiotic. Fuzzform (talk) 01:02, 1 April 2008 (UTC)

Well, if that's your opinion, oh well. But there is nothing messy about the term recreational use at all, it just describes using something recreationally. The term "Abuse" is the messy one not suited to Wikipedia.--68.217.131.246 (talk) 02:40, 28 November 2008 (UTC)

FYI, the packaging on this drug clearly states, as a legal requirement, that it cannot be mixed with alcohol. Suggesting that mixing it with alcohol could be a "recreational use" is misleading, could result in death or injury, and could be misinterpreted as "fun" by idiotic teenagers who don't know the difference between a recreational drug like marijuana and something that could kill you. —Preceding unsigned comment added by 72.209.32.86 (talk) 22:15, 15 October 2009 (UTC)

-If anyone can get any information on long term use/abuse and the permanent consequences they should put it in a section of its own. —Preceding unsigned comment added by Jazzyspaz 2007 (talk • contribs) 08:45, 23 July 2008 (UTC)

There seems to be a missing connection between "in the 1960s it was found that diphenhydramine inhibits reuptake of the neurotransmitter serotonin." and "This discovery led to a search for viable antidepressants with similar structures and fewer side effects,". —Preceding unsigned comment added by 90.14.176.221 (talk) 15:00, 12 December 2009 (UTC)

the picture

The current picture of Diphenhydramine is incorrect. The picture shown is of Diphenhydramine hydrochloride. a correct picture can be found here http://www.humboldt.edu/~morgan/images/ben3_s05.jpg I don't know how to change the picture, but if someone else does, please change it to the above mentioned.

---

At least the picture should be consistent with the chemical formula immediately below it. —Preceding unsigned comment added by 69.12.128.178 (talk) 19:03, 6 October 2007 (UTC)

aren't they the same thing? Disturbed286 (talk) 11:37, 7 December 2008 (UTC)

No, the old pic showed the HCl portion of the molecule, which itself is inactive and not a part of the actual diphenhydramine molecule.--Metalhead94 ^{T C} 22:13, 10 December 2008 (UTC)

Side effects

Regarding the Side effects section: The two paragraphs about Dramamine and Benadryl have little or nothing to do with side effects. May I make a motion that they be moved? -- JEBrown87544 04:46, 3 March 2007 (UTC)

Yeah, they should be moved up to the top or something, but deff not in side effects. -- Kevin ^(TALK)_(MUSIC) 01:11, 19 March 2007 (UTC)

I feel that the section regarding the ironic side effect of hives is written in a substantially different done from the rest of the article, and that its use of the second person seems out of place in an encyclopedic context.71.42.119.67 21:17, 27 April 2007 (UTC)

I removed the line "Despite its use and effectiveness as a sleep-inducing agent, a warning of the potential loss of alertness is rarely prominently displayed on packaging when this drug is sold as an antihistamine", as the box that I'm staring at right now has that listed as the first side effect. "Rarely" is kind of a weasel word anyway. --JD79 01:12, 24 August 2007 (UTC)

The side effects section really needs some statistics. I don't think hallucinations can be all that common. Persephone12 (talk) 15:34, 19 July 2010 (UTC)

Pregnancy Category

As I write this, the US pregnancy category appears correct (to agree with http://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?id=2183 , anyway). However, I don't see a citation on the main page. What's the story with citing information on pregnancy categories? Epylar 05:38, 30 April 2007 (UTC)

Different Image

I think we need an image (for this artcle) without HCl in it(to replace the current image at the beginning of the article).Edward Bower 18:33, 8 May 2007 (UTC)

Tylenol image placement

I switched the side effects and recreational use sections to avoid the preception of an implied endorsement of recreational use, but mainly to allow the Tylenol PM image to be moved to a more appropriate section. With the image's previous placement in the recreational use section, people could get the impression that the number of Tylenol PM pills shown in the picture could be used for recreational purposes, which is not only false but dangerously so. The maximum adult dosage of acetaminophen is contained in only two Tylenol PM pills, and acetaminophen has a much lower overdose tolerance than other medicines, leading to severe liver damage, coma, or even liver failure and death. --71.56.182.67 23:45, 9 May 2007 (UTC)

Tylenol Image

To the above poster, the image was of Tylenol "Simply Sleep" which, in fact, contain NO acetaminophen. Whether or not an image is needed is debatable, but the image that was previously displayed IS what is commonly used by recreational users. Nubz0r 05:13, 28 May 2007 (UTC)

Dosage

Back on the 29th of December 2006 I edited the dosage under 'Recreational Use' from "225mg - 450mg" to "100mg - 450mg" as I believe that to be more appropriate. It was brought to my attention that both my edit and a subsequent edit were both reverted by user 131.191.11.131. The sentence now cites the erowid diphenhydramine vault for dosage amounts, even though that source says that 225mg is in the "strong" range of dosage and 100mg is in the "light" range. So, again, I find it more appropriate that this sentence say "100mg - 450mg" as opposed to "225mg - 450mg". I will make this edit barring any objections. --75.69.170.233 04:36, 10 July 2007 (UTC)

50 mg is enough. 450? You must be kidding. —Viriditas | Talk 14:20, 31 December 2007 (UTC)

50mg is the recommended dose in the U.S. It is not a recreational dose. And 450mg is a moderate/heavy recreational dose, however, it is not uncommon for recreational users to use 600mg or more.--Metalhead94 ^{T C} 22:13, 30 November 2008 (UTC)

having used dph recreationally, i feel i should help shed some light on the topic of recreational dosages. of course, everybody reacts differently and dosages will vary, but a recreational dose is generally around 500-800mg. 50mg is nowhere near enough and is just over a therapeutic dose. 100mg is too light to make give an effect on most people and 500-800mg is most often used. —Preceding unsigned comment added by 81.110.90.75 (talk) 15:27, 20 August 2010 (UTC)

On the subject of doseage, the maximum reccomended doseage in the UK is 50mg, the current wording makes it sound like it's 100mg. A citation would be nice too. —Preceding unsigned comment added by 78.148.127.100 (talk) 13:06, 27 January 2011 (UTC)

Contraindications

A section on contraindications is very much needed in this article since alcohol and depressants have a huge impact on the effects of this drug. —Preceding unsigned comment added by Datapharmer (talk • contribs) 01:58, August 25, 2007 (UTC)

I agree. —Preceding unsigned comment added by 66.58.238.74 (talk) 07:17, 7 July 2009 (UTC)

Neat Trick - applying locally instead of systemically

A neat trick I found a few months ago: break a benadryl (or similar) in half, and use the "open" end to scratch at insect bites or other localized allergic skin reactions. It doesn't have to be very hard or very long. After a few minutes the affected area won't itch anymore for a long time, and you avoid the nasty side effects some people get from systemic Diphenhydramine use. This note is partially a hopefully helpful FYI, and partially establishment of prior art, lest someone try to patent this method. TTK 19:40, 8 September 2007 (UTC)

Well that does make good sense, but there is a topical formulation of DPH available nonetheless. --Seven of Nine 03:51, 14 September 2007 (UTC)

Actually there's a cream, a gel, and a spray. But this doesn't seem to be mentioned in the article, so thanks! --Galaxiaad 16:32, 19 September 2007 (UTC)

dosage and warnings

Please expand this article with information on comparing the dosage between diphenhydramine HCl and diphenhydramine citrate; for example, what dose of diphenhydramine HCl is bio-equivalent to 38 mg of diphenhydramine citrate? Also, please provide more information regarding the incidence of ventricular fibrillation or heart attacks, including information on what types of pre-existing conditions or drug interactions might increase the likelihood of diphenhydramine causing ventricular fibrillation. 69.140.152.251 06:17, 16 September 2007 (UTC)

Under side effects it says "diphenhydramine is a potent anticholinergic agent" and it links to that page. http://en.wikipedia.org/wiki/Anticholinergic (forgot to sign in before posting this) (talk) 07:18, 8 January 2008 (UTC)

Drowsiness

Have there been studies on what percentage of the population experiences drowsiness from diphenhydramine? I personally don't experience any, but my impression is that for most people it's quite intense. Also, what is the mechanism that causes drowsiness? --Galaxiaad 16:52, 19 September 2007 (UTC)

The mechanism which causes drowsiness is the unselective inhibition of H1 receptors in both the PNS and CNS. Inhibition in the CNS causes drowsiness.--Metalhead94 (talk) 00:10, 13 August 2008 (UTC)

Actually I believe the majority of the sedation is caused by diphenhydramine's muscarinic acetylcholine antagonism which affects the CNS in a way that causes sedation. I don't think histamine blocking is directly responsible for drowsiness, it's because first generation H1 anti-histamines just posses a strong anti-cholinergic due to their structure. Sincerely and truly yours, C6541 (T↔C) at 05:35, 13 March 2009 (UTC)

You may be correct. Most older antihistamines have similar structures and thus some level or another of anticholinergic action. However, it should also be noted that these older agents weren't selective with the Histamine receptor system, while newer agents directly target the histamine receptors outside of the CNS.--Metalhead94 (talk) 02:06, 3 September 2009 (UTC)

"Dormin"

I have seen a few different people in the online heroin community referring to diphenhydramine as "dormin". Apparently, heroin is frequently cut with the stuff. Has anybody ever heard of this term for DPH?

Currently, "dormin" redirects to the article on abscisic acid. Confusing.

--63.25.108.100 03:50, 31 October 2007 (UTC)

I have not. You wouldn't happen to have any sources for that information? The page on abscisic acid lists 'dormin' as an alias, which would explain things (though that needs a source too).
-FrankTobia 13:04, 31 October 2007 (UTC)

Yeah, in fact, when buying in bulk, dealers have been known to give them out, for you to cut your H with.I'd say this is definantly true, though no official source other than experience and other people's accounts. Not really sure if this has relevance to the article though...

Timeline

When taken at ordinary dosage:

• How quick take effect?
• How quick to take full effect?
• How long last?
• How long effects linger?
• What variables influence these timings?

Please add these basic data to the article. -69.87.204.15 (talk) 01:01, 22 December 2007 (UTC)

Toxicity

What is the LD50? What is the most toxic action? What other acute/chronic toxicities occur at what typical dose levels? -69.87.204.211 (talk) 14:11, 22 December 2007 (UTC)

I believe the LD50 of diphenhydramine is 500mg/kg in rats.--Metalhead94 (talk) 01:08, 3 September 2008 (UTC)

Topical

Since topical use tends to avoid systemic side-effects, is there a way to treat the nose/sinus area topically? Nasal spray? Nasal irrigation? If you just applied a salve to the nose area, how big of an interior region would get dosed? -69.87.204.211 (talk) 14:11, 22 December 2007 (UTC)

Cost

The current 2007 generic cost in retail drug stores in the US seems to be about 15 cents each for individually packaged caplets, in quantities of two to four dozen. But it is said that ordering non-individually-packaged version in a bottle, from drug store or Costco-type bulk-supply store might get the cost down to almost as low as 1 cent each (presumably this is all for standard US dose of 25 mg). -69.87.204.211 (talk) 14:11, 22 December 2007 (UTC)

Advil PM

Advil PM uses Diphenhydramine Citrate. Is this different from Diphenhydramine Hydrochloride, and should it be mentioned in Common Use? 76.86.119.54 (talk) 07:09, 31 December 2007 (UTC)

There is typically very little difference between a citrate and hydrochloride salt. In the case of Diphenhydramine the active part of the compound is an alkaloid (base). The acidic component is added to form a salt which makes it easier to measure dosage, transport, administer, etc. Many drug manufacturers prefer hcl of over citric acid due to availability and cost, but in the case of Ibuprofen it may not be possible to package it with hcl since Ibuprofen is an acid itself (it could cause it to destabilize or result in other problems). I am not a chemist, so I don't know what the exact reason would be in the case of Ibuprofen. This information seems is more interesting when considering the drug Ibuprofen than Diphenhydramine itself, but may be worth including if it is understood why or if the hcl can't be used in such a combination. Datapharmer (talk) 19:47, 31 December 2007 (UTC)

Cognitive effects

The mental effects are described by many as, "dreaming while awake" involving visual and auditory hallucinations that, unlike those experienced with most psychedelic drugs, often cannot be readily distinguished from reality.

I have to say this is extremely interesting. My guess is that the only reason this drug has not been made illegal is because the delusions are short-lived. Couldn't this be dangerous if it is taken by a delusional person with violent tendencies, or with intent to harm themselves or others within that brief window of time? —Viriditas | Talk 12:11, 31 December 2007 (UTC)

No, the hallucinations are not at all short lived. Depending on dose, the effects usually last anywhere between 6 and 12 hours. Also, when in an anticholinergic delirium, someone is generally not likely to be violent towards other people or objects simply because the stuporous delirium includes such effects as amnesia and interacting with objects or people who aren't really there.--Metalhead94 (talk) 22:41, 21 October 2008 (UTC)

I've heard flashes to earlier events,'paradigm changes',voices, time distortion, laziness. heck, one guy playing his ps for two hours before realising it wasnt on!

It's also not illegal because of the unpleasant physical side effects. 24.118.98.239 (talk) 22:25, 9 February 2008 (UTC)

Other CNS effects occur within the limbic system and hippocampus, causing confusion and temporary amnesia.

It seems to be a form of source amnesia. If it were possible to create false memories, it seems reasonable that diphenhydramine could be used as a catalyst. —Viriditas | Talk

I know I'm making myself appear stupid by saying this, but I once used this drug in a recreational manner. To me the effects were neutral, but bizarre and confusing. Before I knew it I was at my friends house, then I snapped out of it, and being in a state of disorientation, it took me a minute to come to and realize I was at home on the couch. No, it's no fun, and the physical side effects suck.--Metalhead94 (talk) 00:15, 13 August 2008 (UTC)

Merge sections

The recreational use section should be merged into "side effects" and sourced appropriately. —Viriditas | Talk 14:00, 31 December 2007 (UTC)

I disagree. It's recreational use exists and deserves a section of it's own. The 'side effects' section should include side effects when diphenhydramine is used at approved medical doses.--Metalhead94 (talk) 22:48, 21 October 2008 (UTC)

If diphenhydramine is used "recreationally", then it must be used by masochists. There is nothing "recreational" about diphenhydramine; at high levels, it causes delirium, bodily dryness, severe headaches, and makes thinking impossible. Citations are needed, as the current section appears to be a bit fear-mongering.24.62.204.207 (talk) 16:58, 9 July 2009 (UTC)

While most of the side-effects you mentioned may be accurate, personal opinions never make it for long in articles, obviously. It's recreational use exists nonetheless and as such it deserves a detailed section.--Metalhead94 (talk) 15:36, 9 August 2009 (UTC)

Pharmacological Effect

The article as written states that the effect of H1-antihistamine results in reduction of smooth muscle constriction. The effect of Histamine on blood vessels(smooth muscle) is to dilate them and increase blood flow causing inflammation as I understand. It seems the presence of H1-antihistamine will not reduce constriction of blood vessels, but rather prevent their dilation? —Preceding unsigned comment added by 208.54.14.126 (talk) 00:34, 31 January 2008 (UTC) Correction to Pharmacological Effect: H1-antihistamine will "increase" smooth muscle constriction if the drug is correctly listed as an H1-antihistamine. If it is blocking the H1-receptor it stands to reason a prevention of dilation would occur. —Preceding unsigned comment added by 208.54.14.126 (talk) 00:47, 31 January 2008 (UTC)

The information concerning diphenhydramine's inhibition of the uptake of serotonin is incorrect, its norepriphrine that it inhibits. Heres a source http://md1.csa.com/partners/viewrecord.php?requester=gs&collection=TRD&recid=A8124963AH&q=diphenhydramine+dopamine+serotonin&uid=787769046&setcookie=yes —Preceding unsigned comment added by 24.39.181.252 (talk) 02:09, 31 March 2008 (UTC)

I'm going to go ahead and edit the "mechanisms of action" section. DrSparticle (talk) 20:59, 15 June 2011 (UTC)

Cough

I have noticed that many children's liquid cold preparations now list diphenhydramine as an "antihistamine/cough suppressant". I never knew that the chemical had any cough suppressing effects, and there is no mention whatsoever in the article about any such effects. Anyone have additional information about this? -Grammaticus Repairo (talk) 15:11, 1 April 2008 (UTC)

Image

If people feel they'd like to use it, I've uploaded a 3D structural image of diphenhydramine and released it in the public domain. I haven't added it myself as I'm not an expert on the manual of style for things like this, but I thought I'd leave a note here so people at least knew it existed.

[[::User:CrazyChemGuy|CrazyChemGuy]] ([[::User talk:CrazyChemGuy|talk]] · [[::Special:Contributions/CrazyChemGuy|contribs]]) 02:27, 11 June 2008 (UTC)

((removed abusive and unconstructive remark by anon user, possibly troll.)) -user:Kasreyn (not logged in).

Sleeping pills not mentioned.

They are a TERRIBLE sleep aid. They make you drowsy and help you sleep but you feel sleepy the next day as a hangover.--69.149.222.191 (talk) 06:40, 29 August 2008 (UTC)

That can happen with any sedative drug.--Metalhead94 (talk) 01:13, 3 September 2008 (UTC)

Hangover varies from person to person, mostly depending on CYP2D6 metabolism. As you can see in the article, the half-life is 2 to 8 hours. If you're on the 8 hour end, you're probably going to have a hangover. 72.154.101.31 (talk) 03:46, 16 February 2009 (UTC)

• Maybe you are forgetting that diphenhydramine's primary action does not work on a mechanism for effectively inducing sleep. The reason people get classic sleep aids such as most GABA agonists (GHB, benzodiazepines, barbiturates, etc) is because: The drug's prominent effect is nighttime drowsiness caused by reduction of acetylcholine indirectly caused by inhibiting histamine + diphenhydramine being generally safe + being OTC = marketing as a sleep aid. This is in my opinion incorrect though because drowsiness isn't all to helpful for inducing sleep in people who cannot sleep and is actually annoying being drowsy and not being able to sleep at the same time and plus I think marketing a drug for one of it's side effects is irresponsible because it's a side effect not the primary action of the drug. Strangely no one markets opioids for depression despite their euphoric "side effects"
• By the way it does not have a hangover as I state before, it is not a GABA agonist; what you think is a hangover is actually caused by the fact the drug is poor at inducing sleep, ergo leading to lack of sleep, ergo next day drowsiness. Sincerely and truly yours, C6541 (T↔C) at 05:27, 13 March 2009 (UTC)

Sominex

The common usage/dosage section refers to Sominex as a brand which uses Diphenhydramine as the active ingredient. I just added that this is only the US version of Sominex, not the UK version, which uses Promethazine.

Adz657 (talk) 20:58, 9 September 2008 (UTC)

Excitability

Does anyone know why diphenhydramine causes excitability in some individuals? This would probably be worth mentioning in the article. 68.214.70.59 (talk) 10:04, 6 April 2009 (UTC)

I have added excitability to the list of side effects. I also added a reference for it as well. However, as far as why it causes that particular side effect, we would have to find a reliable source for it, if it is to be added to the article.WackoJackO 12:11, 6 April 2009 (UTC)

Messed-up section

Diphenhydramine has sedative properties. The drug is also used as a sleep aid and is an ingredient in many sleep aids, such as Unisom gelcaps (however, the tablet form of Unisom contains Doxylamine, a different active ingredient[7]), and most notably Tylenol PM where it is combined with acetaminophen (paracetamol), Nytol and the US version of Sominex (not to be confused with the UK version which uses promethazine) which have diphenhydramine as the only active ingredient. Several generic and store brands of antihistamines and sleep aids also contain solely diphenhydramine, such as Tylenol Simply Sleep.

Diphenhydramine is widely used in nonprescription sleep aids with a maximum recommended dose of 50 mg (as the hydrochloride salt) being mandated by the FDA. In the United Kingdom, Australia, New Zealand, South Africa, and other countries, a 50 to 100 mg recommended dose is permitted.

These two paragraphs have multiple issues. First, the second is something of a restatement of the first and the two don't flow very well. "...is also used as a sleep aid and is an ingredient in many sleep aids" is awkward to say the least. "...and most notably..." Why most notably? Also the last series in that sentence is contradictory: "and...Tylenol PM where it is combined with acetaminophen..., Nytol, and the US version of Sominex...which have diphenhydramine as the only active ingredient. This states both that Tylenol PM has an additional ingredient and also that it doesn't (the sentence at one time read "...and Nytol and Sominex, which was accurate but pretty awkward with three "ands" connecting the various elements of the series. Last, Tylenol Simply Sleep is neither a generic or store brand so shouldn't be used as an example of those.

Suggested rewrite something like

Diphenhydramine has sedative properties and is widely used in nonprescription sleep aids with a maximum recommended dose of 50 mg (as the hydrochloride salt) being mandated by the FDA. In the United Kingdom, Australia, New Zealand, South Africa, and other countries, a 50 to 100 mg recommended dose is permitted.

The drug is an ingredient in several products sold as sleep aids, either alone or in combination with other ingredients such as acetaminophen (paracetamol). An example of the latter is Tylenol PM. Examples of products having diphenhydramine as the only active ingredient include Unisom gelcaps (the tablet form contains doxylamine, a different active ingredient), Tylenol Simply Sleep, Nytol, and Sominex (the version sold in the US — that sold in the UK uses promethazine). Both types are also sold as generic or store brands.

(comments welcome - I may go ahead and make the above changes later) Gr8white (talk) 00:57, 10 August 2009 (UTC)

International names

I found these other names. Hope it helps somebody. Source: http://www.umm.edu/altmed/drugs/diphenhydramine-043500.htm#Group1Ordinal34

Alergil® (HN); Alledryl® (IL); Allerdryl® (CA); Allergan® (IT); Allerjin® (TR); Allernix (CA); Arcodryl® (ID); Azaron® (BE); Bedorma® (CH); Belarmin Expectorant® (CY); Benaderma® (PT); Benadryl® (AR, BR, CA, CO, ES, GB, HK, ID, IN, TH, TR); Benadryl N® (CH, CZ, DE); Benison® (TR); Benocten® (CH, CR, CY, JO, KW, LB, SG, SV); Benylan® (DK); Benylin antihistaminicum® (BE); Benzantine® (IL); Betadorm D® (DE); Betasleep® (ZA); Butix® (FR); Caladryl® (AR, EG, ES, NL, TR, ZA); Calmaben® (AT, SK); Cathejell® (AT, DE, IL); Daslin® (IN); Dermodrin® (AT, PL); Desentol® (SE); Dibondrin® (AT); Difenhidramina Denver Farma® (AR); Difenhidramina Fada® (AR); Difenhidramina Richmond® (AR); Difenidramina® (BR); Difenidramina Cloridrato® (IT); Dimedrol® (RU); Dimidril® (HR, SI); Dimiril® (IN); Diphamine® (BE); Diphenhydramine-Asta Medica® (LU); Dolestan® (DE); Dormutil N® (DE); Dramina® (SI); Emesan® (DE); Fabolergic® (AR); Fenotral® (TR); Halbmond-Tabletten® (DE); Hemodorm® (DE); Hevert-Dorm® (DE); Histaler® (AR); Histam® (DO); Histaxin® (AT); Medinex® (GB); Mudantos H® (AR); Nautamine® (FR); Neo Respir® (AR); Neosayomol® (ES); nervo OPT® (DE); Noctor® (AT); Nuicalm® (BE); Nustasium® (BE); Nytol® (CA, ES, GB); Nytol® Extra Strength (CA); Nytol SM® (CH); Otede® (ID); Pasifen® (CL); Paxidorm® (SG); Pedeamin® (BD); Phenadryl® (BD); PMS-Diphenhydramine (CA); Prurex® (AT); Psilo® (BG); Purigel® (BE); ratioAllerg® (DE); R-Calm® (BE); S.8® (DE); Schlaftabletten N® (DE); Schlaftabletten S® (CH); Sedativum-Hevert® (DE); Sediat® (DE); Sedopretten® (DE); Sidiadryl® (ID); Simply Sleep® (CA); Sleepeze-PM® (ZA); Sleepia® (CH, DE); Somol® (CL); Sonodor® (ES); Tzoali® (MX); Unisom Sleepgels® (AU); Vivinox® (DE)

217.73.30.82 (talk) 06:24, 21 October 2009 (UTC)

Half-life

The ref for the half life says: "The elimination half-life has been reported to range from 2.4-9.3 hrs." This is not suitable for reference since it does not cite any specific report (it is a secondary source with no primary source). Attys (talk) 02:59, 16 September 2010 (UTC)

Replaced. This is standard practice for prescribing information and drug formularies, though. Few cite their primary sources. Fvasconcellos (t·c) 04:02, 16 September 2010 (UTC)