Viagra is a drug used to treat male erectile dysfunction, developed by the pharmaceutical company Pfizer. The generic name for this compound is ''sildenafil''. It is a blue pill with the words "Pfizer" on one side and "VGR xx" (with xx being either 25, 50 or 100 as the miligram dose of that pill) on the other.

Chemical name: 1-[4-ethoxy- 3-(6,7-dihydro- 1-methyl- 7-oxo- 3-propyl- 1H-pyrazolo [4,3-d]pyrimidin-5-yl) phenylsulfonyl]- 4-methylpiperazine citrate. Molecular formula: C22H30N6O4S.C6H807. MW: 666.7

Mechanism of action
Part of the physiological process of erection involves the release of nitric oxide (NO) in the corpus cavernosum. This then activates the enzyme, guanylate cyclase, which results in increased levels of cyclic guanosine monophosphate (cGMP) which results in smooth muscle relaxation in the corpus cavernosum which leads to increased inflow of blood which leads directly to erection.

Sildenafil is a potent and selective inhibitor of cGMP specific phosphodiesterase type 5 (PDE5) which is responsible for degradation of cGMP in the corpus cavernosum. This means that, with Viagra on board, normal sexual stimulation leads to increased levels of cGMP in the corpus cavernosum which leads to better erections. Without sexual stimulation and no activation of the NO/cGMP system, Viagra should not cause an erection.

Contraindications
- when taking other nitric oxide donors, organic nitrites and nitrates (which includes glyceryl trinitrate, sodium nitroprusside, amyl nitrite)
- in men for whom sexual intercourse is inadvisable due to cardiovascular risk factors
- severe hepatic impairment
- severe impairment in renal function
- hypotension
- recent stroke or heart attack (myocardial infarct)
- hereditary degenerative retinal disorders (including genetic disorders of retinal phosphodiesterases)

Dose
The dose of viagra is 50mg to 100mg taken once per day between 0.5 to 4 hours before sexual intercourse. If taken with a high fat meal, there may be a delay in absorbtion of Viagra and the net effect might be muted slightly as the plasma concentration will be lowered.

Adverse effects
Amongst viagra's serious adverse effects are: priapism, severe hypotension, myocardial infarction, ventricular arrhythmias, sudden death, stroke and increased intraocular pressure.

Common side effects include headache, flushing, dyspepsia, prolonged erections, palpitations and photophobia. Temporary visual changes including blurring of vision and a curious bluish tinge have also been reported.

Metabolism and excretion
Viagra is metabolised by hepatic enzymes and excreted by both the liver and kidneys.


Is it any coincidence that the choice of virtual reality over reality in The Matrix is a blue pill?

Viagra®

Brand Name: Viagra®
Active Ingredient: sildenafil citrate
Strength(s): 25mg, 50mg & 100mg
Dosage Form(s): Oral tablet
Company Name: Pfizer Inc.
Availability: Prescription only
Date Approved by FDA: March 27, 1998

What is Viagra used for?
Viagra is used to treat impotence in men. Viagra increases the body’s ability to achieve and maintain an erection during sexual stimulation. Viagra does not protect you from getting sexually transmitted diseases, including HIV.

Who should not take Viagra?
Men who are currently using medicines that contain nitrates, such as nitroglycerin should not use Viagra because taken together they can lower the blood pressure too much. Viagra should not be used by women or children.
Reports of Patients’ Experiences Since Viagra Became Available:
In patients taking Viagra, several heart-related side effects have been reported, including heart attack, sudden death, irregular heart rhythm, stroke, chest pain, and increased blood pressure. It is not possible to determine whether these events are directly related to Viagra, to sexual activity, to the patient’s heart condition, to a combination of these factors, or to other factors.
The following factors are associated with increased blood levels of Viagra:
age greater than 65 years
liver problems (such as cirrhosis)
severe kidney problems
taking certain medications at the same time (e.g., ketoconazole, itraconazole, erythromycin and saquinavir).
In these patients, the recommended starting dose of Viagra is 25 mg.

Special Warnings:
Viagra was not studied in patients who have a history of the following conditions:
Heart attack, stroke, or life-threatening irregular heart rhythm within the last 6 months
Very low and very high blood pressure
Heart failure or unstable chest pain
Certain eye disorders
Viagra can cause a rare but serious condition of prolonged erection (priapism). It is important to contact your health care provider immediately if your erection lasts longer than 4 hours.

Possible side effects:
Headache
Flushing
Upset stomach
Stuffy nose
Urinary tract infection
Visual changes such as mild and temporary changes in blue/green colors or increased sensitivity to light.
Diarrhea


More information can be found at www.fda.gov/cder/ or on the package insert.
Viagra is a great little pill for those men who are experiencing erectile dysfunction. It is also known to increase sensitivity and make sex excellent, even into a man's twilight years. Many younger males have gotten ahold of this drug, and have begun to experiement with it, including one person known to a good friend of mine.

This friend of a friend, got the Viagra from somewhere over the Internet. He tried it with a few other drug combinations, and played around with it. Then for the sake of the adventurous drug user, he gave some to his girlfriend, and then feared for his life: Viagra has an affect on them too.

It turns out that Viagra in women has an odd sexual side effect; it turns their sex drive into overdrive, like nothing else they had ever seen. He confirmed this by later discussing with other experimenting people over the Internet. They had "fablous" sex, according to the woman, who could simply not get enough. To my poor friend, he had to stop, because Junior was too sore and chaffed to keep going. That's right, chaffed by a turned-on woman; a lot of sex. Needless to say, it was an amazing experience, for them both.

They have tried it several times, and his girlfriend is hooked on the increased appetite the drug gave her. This, however is dangerous, and not without its potential side effects. Misusing any drugs with sexual side-effects can be (permanently) damaging. They were lucky, and enjoyed it heavily.

I am not responsible in any way for anything that you do to yourself with Viagra. This story is also a tad second-hand, but amusing nonetheless. Do research first to see if this sort of thing interests you.
Viagra (sildenafil), a prescription medication that enhances the quality of erection, was first introduced onto the U.S. market by Pfizer in 1998, becoming what wags described as the first purely recreational drug to gain approval from the FDA. The name "Viagra" is a portmanteau synthesized from "Niagara" and "vigorous", intended to carry connotations of strength and energy.

Viagra was originally marketed towards elderly and aging males as a treatment for erectile dysfunction. The FDA had in 1997 lifted its long-standing prohibition of direct-to-consumer advertising of prescription drugs, and Pfizer took advantage of the new possibilities by running an initial advertising campaign featuring the endorsement of former U.S. Senate majority leader, failed 1996 presidential candidate, and prostate cancer survivor Bob Dole. The dual taboos of open talk about erections and of sex among the elderly, combined with the role of Dole, who had by this point reinvented himself as a somewhat comic figure, made Viagra a goldmine for not particularly creative comedians, and Viagra jokes were a staple of late-night talk shows for months if not years.

While Viagra's public image may have been a common topic of jest, what could not be dismissed so lightly was Viagra's commercial success, coming at a dark time for a pharmaceutical industry facing the imminent expiration of patents on several popular medications. Viagra brought Pfizer over 1.5 billion dollars in sales annually, and competitors hurried "me-too" drugs Levitra (vardenafil, from GlaxoSmithKline and Bayer), and Cialis (tadalafil, from Eli Lilly) through testing and onto the market.

Once Pfizer had firmly established Viagra and sponsored initiatives to significantly dispel taboos and a previously common sense of embarrassment surrounding weak erections, it sought to expand its market to younger men who might not have otherwise considered their unsatisfactory erectile capabilities as a disorder for which they should seek treatment. In contrast to the septuagenarian Dole, figures in later advertising campaigns appeared to be closer to their forties and fifties, and the ads' tone became more playful.

Of course, even this cutoff point was largely arbitrary. Before the introduction of Viagra and its competitors, a trend towards decreased erectile capability and libido and increased difficulty in achieving orgasm that came with age was largely considered a natural, if regrettable, state of affairs, not a medical condition. "Erectile dysfunction" was in large part a definition created and promoted by Pfizer to create a vocabulary by which to legitimate Viagra by medicalizing unsatisfactory erectile function, and as such does not have a solid, hard and fast definition.

Elderly men previously unable to achieve the strength of erection necessary to achieve satisfactory penetration report that Viagra allows them to engage in coitus again, but at the same time 20- and 30-something men who might traditionally have been considered perfectly sexually capable have found that Viagra can lend a strength and rapidity of erection previously considered the exclusive province of 17-year-olds, the age at which male sexual function is considered to reach its peak. In both cases, users report increased pleasure during sex on behalf of both themselves and their partners, a heightened sense of virility and sexual competence, and a resultant increase in confidence and self-esteem.

There is some evidence to suggest that Viagra may also have some benefits for female users - anecdotal reports have indicated heightened sexual drive, increased pleasure during sex, and greater ease in attaining orgasm. The mechanism for these effects is yet unclear. It may stem from increased blood flow to the clitoris, labia, and other structures of the female genitals. On the other hand, it might be some entirely separate mechanism, or simply a placebo effect. With thoughts of a possible doubling or more of their potential market, pharmaceutical companies are currently studying the female use of Viagra and similar compounds closely.

Another popular unapproved use, especially among young people, is that of taking Viagra in conjunction with recreational drugs like ketamine, cocaine or methamphetamine whose circulatory or anesthetic effects inhibit erection. The combination of Viagra with Ecstasy (MDMA), a popular recreational stimulant which augments tactile and emotional sensitivity but inhibits tumescence, has been especially highly praised. The prominence of such Viagra cocktails is perhaps most pronounced in gay dance club culture, where amyl nitrite had historically been used in a similar role.

Viagra isn't a perfect wonder drug, though. Unlike previous attempts at erection-inducing medications, Viagra does not directly cause erection, but simply makes it possible - physical, mental, or other stimulation is still necessary, and Viagra will not cure psychological impediments to erection. Further, Viagra's "window" of effect is somewhat limited, and users are directed to take the pill at least thirty minutes and no more than four hours before, erm, making use of its effects. Given the degree to which sexual intercourse is considered to properly be an impulsive, passionate, unplanned activity, users may find these constraints limiting. For the horndog in a rush, Viagra can be insufflated to produce more immediate effects, but there is yet no clear way to extend its period of effect aside from repeated administration, which may aggravate unwanted or dangerous side effects. Those interested in prolonged periods of effect may want to consider Viagra's newer competitor Cialis, nicknamed "the weekender" for its 36-hour effective duration.

Though Viagra has shown benefits in a wide range of users, its legitimation within a medicalized disease/treatment framework means that the bulk of the millions of its prescriptions written yearly go to older men. However, not all users acquire Viagra in this manner. Viagra's popularity even among those who might not consider themselves recreational drug users is considered a major factor in the growth of "internet pharmacies" - online retail operations, often hosted on flag of convenience servers, selling medications with only the most perfunctory (if any) nods towards legal requirements regarding physician approval. In the face of lingering taboos regarding discussion of the genitals and a culture in which weakness of erection is often considered symbolic of low value and failure as a male, the anonymity these services offer can't hurt, either. Viagra is such a staple of internet commerce that a poorly spelled solicitation for its purchase is generally considered the spam archetype.

Log in or register to write something here or to contact authors.