Talk:Sildenafil

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Contents

[edit] Prescription in every country?

I have heard that the generic for Viagra does not require a prescription in all countries, espcecially in Europe. Is this so?


[edit] Dosage info in article

Is it wise for Wikipedia to have dosage recommendations for Viagra, which is a perscription medication? Dispensing medical advice can be very risky, espcially for a public-domain forum like this one. (It could also encourage spammers to edit in their own 'recommendations.')

Yes it is perfectly acceptable. You go to any drug encyclopedia in the library and they always give recommended dosage. In fact it is useful. One time years ago I looked in one of those books for dosage because the dosage on the lable sounded off. I checked online and then called the doctor who said it WAS the pharmacy that was in error, but he said it the extra dosage wouldn't have harmed me. So it is not only within encyclopdia standard but it's helpful as well

4.143.229.216 23:42, 6 April 2007 (UTC)Nick

I think the only criterion should be truth. Is the information given in the "Dosage and price" section objectively true? I don't know, but if it is, then it should stay. AxelBoldt 11:05 Aug 21, 2002 (PDT)
If its a perscriptions, it shud not be listed in here you shud only find it if you ar perscriptions. Altho thay mite rite in the ensiclopedia wat is usaly is and wat efect is usaly is, evin tho you shud not actely do that, becuse enybudy reeding shud no to prescripsen instrucsens insted.

[edit] Origin of name

Does anybody know the origin of the name "viagra"? Yes, "viagra" comes from the contraction of two words VIGOR and NIAGARA, for the word VIGOR it doesn't need to be explained and is NIAGARA from the waterfall giving an impression of a fontaine of hennessy happiness with an impressionant rate, also the first letter V is for VICTORY for those who couldn't before and the form of the legs open from a woman.

[edit] Moved to sildenafil

Policy seems to be that in the naming of drugs, the generic name is used. This limits intercontinental confusion and decreases the smell of advertising (and spam, see above).
JFW | T@lk 22:09, 3 May 2004 (UTC)

Should this be under Sildenafil citrate? Sildenafil citrate was redirecting to Viagra so I switched it to redirect to Sildenafil. Frunge.

You're right, I should have tidied up the double-redirects. Generally, it seems wikipedia names pharmaca (drugs) after the active ingredient. IMHO it would be folly to name all adjuvants (enalapril malleate, atorvastatin calcium, imatinib mesylate). Correct me if I'm wrong—the Wikiproject Drugs never really hit off, and whenever I do pharmacology subjects I just follow my intuition.
JFW | T@lk 09:36, 4 May 2004 (UTC)

One disadvantage of putting naming the article 'Sildenafil' is that if you browse Category:PDE5_inhibitors, it's not immediately obvious that Viagra and Cialis (as they are currently best known, due to spam) work on similar principles, unless you happen to know the drug name. - Jon Dowland 14:33, 9 November 2005 (UTC)

[edit] price info is US-centred

For example, in India the various sildenafil citrate brands all cost much less than 90 US-cents for a 100 mg pill. That is because India still allows only process patents, no product patents. (A product-patent ordinance was issued on 30 Dec 2004, but when the parliment will be in session in a month or so; it will have to be replaced by a bill - and the bill will have to be passed by majority vote in both houses of parliament - just like in the UK. We shall see.)

[edit] Viagra-Blindness

How do we manage Viagra-Blindness issue? Is it acceptable to post that there are rumors that... See http://www.cbsnews.com/stories/2005/05/26/eveningnews/main698124_page2.shtml for instance --Dennis Valeev 22:02, May 27, 2005 (UTC)

[edit] Spam, spam, spam...

There seems to be no end to the Viagra linkspam. Is there anything we can do about this besides constantly reverting the page? ~K 03:45, 29 July 2005 (UTC)

Get it protected, I believe, if it's happening regularly enough within a short time-span.


How about mentioning the prevalence of viagra | cialis | levitra in spam email? I know I'm not the only person in the world who gets multiple spam emails a day from third-rate web sites trying to sell me these drugs over the internet without a prescription. Obviously, I don't want to endorse the sites, but rather point out the fraudulent use of it online...
How about mentioning the neverending (and utterly annoying) Internet propaganda for Viagra-likes on this page ? —Preceding unsigned comment added by 79.85.53.146 (talk) 10:38, 3 January 2008 (UTC)

[edit] For fact-checking

In some countries like Mexico, India where the patent on Viagra have expired, big drug manufacturers manufactured, where it is marketed under the brand name Caverta, Silagra, Edegra, Kamagra, Meltabs. These pills contain exactly the same ingredients as the branded one but cost a quater of the original branded one. --Calton | Talk 15:04, August 24, 2005 (UTC)

[edit] Image

The image of the sildenafil molecule was deleted. Who is going to upload a new one? I can have a go, but my MDL ISIS 2.5 is not exporting images to PNG for some odd reason. JFW | T@lk 22:35, 24 September 2005 (UTC)

Done. ~K 00:08, 25 September 2005 (UTC)

[edit] Scored?

This line looks wrong: Sildenafil is not scored, meaning there is no guarantee that the drug is evenly distributed throughout the tablet, therefore it is not advisable to cut it to change dosage. Is there some meaning of "scored" I'm not familiar with? I thought if a pill was scored it meant the pill was notched to allow easy splitting, nothing about even distribution of the active drug. Am I missing something? Fan1967 03:11, 10 March 2006 (UTC)

You're correct about the meaning. The issue being raised is that if the composition of the pill is not homogeneous and one physically cuts it in half, one may not get "half the dose". Whether this is the reason the pill is not scored here...dunno. DMacks 01:43, 10 May 2006 (UTC)


I am just wondering, if this sentence is incorrect, could someone remove it? I don't want to do it because I am not familiar with this drug, and don't personally know if it is right or wrong.
> Sildenafil is not scored and it is not advisable to cut it to change dosage since the active compound is not distributed homogenously in the tablet.
I want to send a link to this page to someone and don't want to scare them about cutting the pill.

Kelliann 19:56, 15 November 2006 (UTC)

The Viagra FAQ notes:
Can I cut my pills in half?
VIAGRA pills should not be cut in half. No studies have been done to determine if half a pill is effective.
Also, even if it were homogeneous (which I don't know) the actual cutting may be hard to do evenly. A FAQ I found through Google (NB: commercial company, so potential bias towards their special cutter, but underlying issue sounds believable even if their cutter is no better than any other) says:
What about the pill cutter my pharmacists sells for about $10? Will it cut Viagra?
No. Inexpensive pill cutters are available, but they are designed to cut uncoated pills such as aspirin that are already "scored" or notched to facilitate easy cutting. The coating on Viagra is extremely hard and very difficult to penetrate, even with a razor. If you do manage to slice through the hard coating, the ingredients inside the Viagra tablet usually crumble unevenly, making it impossible to get an accurate dose.
DMacks 20:32, 15 November 2006 (UTC)

Reading the article as it is suggests that the only reason for not cutting the pill is difficult. The pill is additionally not evenly distributed with active ingredient - I think that's worth adding back in. Empirical evidence suggests that cutting the pill (normally I use my teeth) does work, but it's almost certainly not advisable... 212.183.134.210 07:28, 17 May 2007 (UTC)


This is clearly marketing-material. Most doctors prescribe the highest dosage strongest pills and then tell you to cut them up, thereby saving a lot of money on the ridiculous price this is sold for in Western countries. Don't believe the marketing spin that "half a pill is not effective", it is a lie. —The preceding unsigned comment was added by 203.101.239.109 (talk)

To the user above - as previously stated, there has been no study to prove that the drug is homogenous throughout the pill in its final state. It IS evenly distributed during the dosing phase, but as each pill is subsequently assessed as a whole unit, if segregation occurs after dosing, this will not be detected.
As for the 'marketing spin' that half a pill is not effective, it depends very much on the theraputic dose of the drug and the individual's unique body chemistry. Half a pill may still be effective in a 60kg middle aged man, but not in a 90kg young athlete. If you decide to split pills in order to extend a prescription, it's at your own risk. Oni no Akuma 09:23, 19 July 2007 (UTC)

[edit] Multi-address spambot

This article appears to be monitored by some sort of spambot with a wide range of IP addresses at its disposal. Within minutes after unprotecting the article today, it picked right back up again. Semi-protection (both on and off) will be tested throughout the week. If this continues through the long term, I suggest that this article be protected in the same manner as George W. Bush. Best regards, Hall Monitor 17:41, 28 March 2006 (UTC)

[edit] Request for more information

I've made a request for more information about how this drug compares to similar ones. I think other people would like to know more about this too. Thanks to anyone who can help. Eje211 16:59, 9 May 2006 (UTC)

[edit] Effects on women

Can anyone provide an authoratative cite to support the claim that Viagra "is also capable of arousing women for greater sexual drive" ? I have seen no research to support this claim and in fact IIRC recent studies show this to be false. 06:59, 22 May 2006 (UTC)

  • I recall a study about 7-8 years ago where it was reported to increase fertility/chance of pregnancy in women. 71.198.127.97 02:10, 6 August 2007 (UTC)
Any chance of a reference or link to the study? Oni no Akuma 11:39, 6 August 2007 (UTC)

Any chance of any mention of women at all? Bitwiseb (talk) 07:10, 7 April 2008 (UTC)

[edit] Death of Sani Abacha

I went looking for a cite for:

Sani Abacha, suspected cause of his death [citation needed]

but couldn't find any. Well, I found mention that a dose of Sildenafil may have led to his death, but only inasmuch as it is the suspected vehicle for an unrelated poison (if one believes that he was poisoned at all).[1] DMacks 17:00, 24 May 2006 (UTC)

[edit] Citation

I've changed the citation style to cite.php throughout. No paper was cited more than once, making this the most preferable referencing system for this article.

I also removed a few papers reporting effects on Raynaud's, given that a randomised controlled trial is available.

We should work on the unreferenced parts of the article. The speculation in its naming is unsourced and could do with a WP:CITE. JFW | T@lk 12:14, 5 June 2006 (UTC)

[edit] Hard drug

The link "hard drug" leads here, but it also refers to illegal drugs that are very potent.

[edit] Removed some text

I removed the following text because it just sounds like one editors guesses. Pls provide a source before reincluding:

The name "Viagra", like many drug names, is a marketing invention. It was possibly inspired by the Sanskrit word "vyāghra", which means "tiger". The word rhymes with "Niagara" (Niagara Falls is a popular honeymoon destination and Niagara, being such an impressive waterfall, evokes a sense of incredible erectile and ejaculatory strength). The sound of the word also suggests the words "vigor" and "virile"[citation needed].

I also removed this, because it is unsourced speculation:

It has been suggested that Viagra would lead to a marked drop in the demand for certain traditional remedies, such as tiger penises and rhinoceros horns and that the drug may therefore help to preserve these endangered species. However, this is unlikely in that these parts of endangered species are not only used to treat impotence. Rhinoceros horns, for example, are used as a treatment for high fever. Furthermore, since Viagra has not been shown to possess aphrodisiac properties, it is unclear that the natural remedies would compete with this new clinical drug.

Ashmoo 04:10, 20 June 2006 (UTC)

I agree with the removal of both. Although plausible, this article needs to be referenced as tightly as possible, and both factoids were unsourced and failed WP:V for a very long time. JFW | T@lk 20:20, 16 July 2006 (UTC)

[edit] More Legislative History Needed

I think more needs to be put into the entry about Viagra's legislative history, by state. For instance, several states have recently halted Medicaid spending on Viagra for conviced sex offenders. I'm thinking in the first "History" section, more about this should be included. Scunning 19:59, 27 June 2006 (UTC)

[edit] Negative studies

Probably shouldn't be included, but sildenafil actually worsens sleep apnea syndrome[2]. JFW | T@lk 19:21, 25 September 2006 (UTC)

[edit] Viagra saves a baby

[3] opened the vessels in the childs lungs allowing it to take in the oxygen being delivered. Could be added to other uses section. Anyone agree?-Ravedave (Adopt a State) 05:50, 17 February 2007 (UTC)

This use is in fact mentioned above, albeit in medical terminology. One single newspaper article doesn't necessitate adding a section like "viagra saves baby" or some nonsense like that. Maybe if it were routinely used, it would be notable. Perhaps that link should just be in the links section? Fuzzform 01:17, 24 March 2007 (UTC)

[edit] Page is a mess...

This page is full of junk information about anecdotal use of Viagra, rather than any substantial information about the compound. For example, why is there a description of the pill in the first paragraph? This is not something you would find in any other page about a pharmaceutical. And why is there information about cutting the pill in half? It's probably sustained release, anyway. Fuzzform 01:17, 24 March 2007 (UTC)

[edit] UK?

Given that sildenafil was first synthesized in England, why is there no info about when it was approved by the authorities there? The History section goes straight from the British trials to the American FDA approval, which looks silly. Oh, and in reply to the "More Legislative History" bit above: why only "by state"? The US isn't the only country where Viagra is used! 81.158.3.1 13:20, 26 March 2007 (UTC)

People write what they know and/or can find references to support. If you have additional information on a topic or feel something is written poorly, feel free to edit the article to include or improve whatever you think is appropriate...that's how Wikipedia works. DMacks 13:40, 26 March 2007 (UTC)

[edit] Unique SMILES formula

There are multiple possible ways of writing a SMILES formula, but one of them is a canonical form intended for database lookup. This "Unique SMILES" formula, which might be a better choice to put in the infobox, is CCCc1n[n](C)c2C(=O)NC(=Nc12)c3cc(ccc3OCC)S(=O)(=O)N4CCN(C)CC4

71.41.210.146 05:08, 29 April 2007 (UTC)

[edit] Another competitor drug

Yohimbine is another drug that improves erectile function. It is also inexpensive, and available over the counter in France (I don't know about other countries). —The preceding unsigned comment was added by 81.57.227.118 (talk)

added --Selket Talk 20:29, 4 June 2007 (UTC)

Yohimbine is no longer recommended for prescription to remedy Erectile Dysfunction. More information on Yohimbine is available on Wikipedia Wiki Article, but alternatives should be confined to the Erectile Dysfunction page surely? --Glowplug1 20:45, 9 July 2007 (UTC)

[edit] Further ancectdotal history?

I've got an anecdote about the discovery of viagara's effect on erectile disfunction - should/could this be added to the history of the drug? During the First in Man pre-clinical trial, it was noticed that all the subjects (all young males as per a FIM trial) were spending a lot of time in bed. The attending medical staff became worried about possible side effects the drug may be having - it turned out that all the patients had erections and hence were too embarrassed to move around. I have a source (the doctor in charge of the FIM clinic was a lecturer at my university), but nothing verifiable via the internet. —Preceding unsigned comment added by Oni no Akuma (talk • contribs)

No, everything in Wikipedia should be verifiable. It needn't be verifiable via the Internet, but a reliable source that can be checked must exist for all information. Personally gathered hearsay, regardless of how reliable you regard the source, would not meet those criteria and would probably fall under the verboten category of no original research. If you can find the same story published somewhere in a reliable source, then it would probably be welcomed. --Kbh3rdtalk 21:56, 8 June 2007 (UTC)

[edit] No information on what it does

Frankly this article sucks... it mentions [briefly!] what Viagra is approved for and what it does biologically, but no information on what effects it has. Does it simply produce an erection for 4 hours? If not, what then? This is the information the article should have. -Rolypolyman 14:21, 8 July 2007 (UTC)

The article explains what effect it has (it produces an erection), then explains the possible side effects it may have (side effects section) and other possible uses for the drug (Other uses and non medical use).
Adding the pharmacokinetics data to the article may not be appropriate as 1) it's quite technical, 2) a lot of the published data is scattered throughout various journals and collating them together may constitute original research, 3) anybody capable of fully understanding the data will have sources other than Wikipedia to obtain the information from.
If people feel it will contribute to the article, then I'll add it. Oni no Akuma 23:25, 13 July 2007 (UTC)
Wikipedia does have substantial scientific detail for some articles and IMO does well not limitting ourselves to targetting slightly-curious consumers or school essay-writers. A sentence or few about how it works (bio/pharma level stuff) wouldn't be out of place, something to the level of the first paragraph of the Clinical Pharmacology: Mechanism of Action section of the label. I think all scientific terms, enzymes, etc there already have very detailed wiki pages of their own. DMacks 22:57, 15 July 2007 (UTC)
The information in that first paragraph is all mechanism of action, which is already covered in the article. Rolypolyman seems to want additional information beyond this and the information I'm proposing to add would be covered under the Pharmacokinetics and Metabolism section and downwards.
Would this level of detail be appropriate?Oni no Akuma 17:13, 16 July 2007 (UTC)
That would be excessive in my opinion, concur that someone that needs that info can find it somewhere other than Wikipedia rather than WP editors rereresummarizing existing summaries or engaging in OR of our own. The FDA label is already linked from the article (different link than I used, but appears to be the same content?). DMacks 23:55, 22 July 2007 (UTC)
Both the FDA label you've linked and the article link are the same paper, just submitted twice due to regulatory requirements (one's a New Drug Application, the other is normal drug information). Oni no Akuma 07:07, 23 July 2007 (UTC)

My impression is a 4 hour errection is possible, if a person can remain sexually motivated that long. Most of us loose the erection quite quickly if we think about something else. Ccpoodle 20:20, 21 July 2007 (UTC)

Technically yes, if a person can remain sexually interested for the entire period, you can maintain an erection for the entire duration of effect. However from the paper DMacks posted, it states that a duration of effect was ONCE observed for 4 hours. That means at the 4 hour mark, the patient was still better able to get an erection and maintain it than previously without sildenafil, not that he had an erection for the whole 4 hours. Oni no Akuma 22:21, 22 July 2007 (UTC)

[edit] Generic Alternatives

I think its important to cover the fact that generic alternatives exist. Viagra may be the most known brand, but there are others and these should be listed, for example Kamagra (still contains Sildenafil Citrate), which is manufactured by Ajanta Pharma, which many people think is fake (probably as a result of so many scam sites), but which actually isnt. Perhaps Kamagra should have its own page which Sildenafil and the Erectile Dysfunction pages link to? I am happy to edit/supply info. --Glowplug1 20:50, 9 July 2007 (UTC)

One thing to bear in mind about any generics is that since sildenafil is still in patent in the US (and in most other western countries) their legal distribution is limited to those countries (mostly outside the west) which don't honor drug patents and/or have alternate drug patent rules. mr_Handy 23:45, 23 July 2007 (UTC)

[edit] Effect on Oxytocin levels

A new study by the University of Wisconsin-Madison has found a link between Viagra use and elevated levels of oxytocin in rats. Perhaps the section on Viagra-as-aphrodisiac should be amended —Preceding unsigned comment added by 71.202.123.166 (talk) 07:31, August 24, 2007 (UTC)


[edit] Fight Viagra with Exercise

Before you try viagra fight sex problems with exercise. A study of 55 men with erectile dysfunction showed 75% improved or regained normal performance by doing pelvic exercises, or Kegels, each day. —Preceding unsigned comment added by Burty2007 (talk • contribs) 17:26, 23 September 2007 (UTC)

[edit] Here's a laugh

I'm sorry, I couldn't help it. - Cyborg Ninja 22:09, 6 October 2007 (UTC)

[edit] Also good for jet lag!

This year's Ig Nobel Prize in Aviation went to Patricia V. Agostino, Santiago A. Plano and Diego A. Golombek of Universidad Nacional de Quilmes, Argentina, for their discovery that Viagra aids jetlag recovery in hamsters.[4] This is a real study, published in the Proceedings of the National Academy of Sciences.[5] --Itub 13:59, 10 October 2007 (UTC)

[edit] Marketing section?

The lack of a marketing section for something like Viagra seems like a rather large oversight :/ Anyone up for taking a crack at one?--SeizureDog 19:20, 1 December 2007 (UTC)

[edit] error in external links

The link to the "prescribing information" is broken - it should be http://www.pfizer.com/files/products/uspi_viagra.pdf. I'd fix it but I refuse to register an account. —Preceding unsigned comment added by 76.25.248.245 (talk) 05:48, 9 January 2008 (UTC)


[edit] Article lacks any historical data or accuracy

It is not a known fact that British scientists discovered "Viagra"--it is only known that they sythesized it into a pill form once sildenfil was discovered to increase blood flow to the penis, helping men suffering from erectile dysfuntion (ED). Literature on this subject contradicts. It is only documented that researchers for Pfizer's Kent facility are responsible for Sildenfil's synthesis into pill form (Viagra). The sources attributing British scientists with its "invention" come only from the British press; but others, including Pfizer itself, dispute these claims--or they are silent about the truth. Either way, you cannot state something as fact when even Pfizer disputes its accuracy. The controversy surrounding Viagra's development should be discussed more in the article, at least. More importantly, I am shocked the article failed to mention anywhere that sildenfil's original purpose was to treat heart disease, not ED. I read in the article that one of Viagra's contraindications is heart problems. Where is the history here?? Pfizer learned later through trial studies in the United States sildenfil's positive results in the treatment of ED. There needs to be more historical research. —Preceding unsigned comment added by Guidosdad (talk • contribs) 04:23, 23 January 2008 (UTC)

Actually they discovered its ED effects during the First in Man clinical trial in Canterbury. Your points would be perfectly fine to add to the article, provided there's a verifiable source. I don't have such a source and although I heard the story from one of my lecturers, who was the doctor who ran the FiM clinic, I can't add this to the article. Oni no Akuma (talk) 12:41, 23 January 2008 (UTC)