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Viagra was initially developed as a heart medication used to improve blood flow to the arteries.  However during the testing period, it was found that Viagra caused increased blood flow to the male sex organs.  Consequently, the FDA approved Viagra on March 27, 1998 to help treat erectile dysfunction in men. 

Viagra works by increasing the body's ability to achieve and maintain an erection during sexual activity.  Since its initial production, more then 5 million men have turned to Viagra for help. (


What is Erectile Dysfunction?  (


            Erectile Dysfunction (ED), or Impotence, is the inability to maintain an erection during sexual intercourse.  Over 30 million men, of varying ages, in the United States suffer from chronic impotence, but only 5%of those have ever been treated. Years ago ED was believed to have occurred in the mind and as a result of growing old.  Although age is still a contributing factor, the majority of ED cases are associated with other conditions.

More recently ED has been linked to psychological factors as well as common health problems, such as prostate cancer, arteriosclerosis (hardening of the arteries), diabetes, spinal cord injuries, pelvic trauma, heavy smoking, and many medications.  ED has also been known to have a negative emotional impact on self- image, self-confidence, and self-worth.  The sexual partners of those with erectile problems often feel in most cases as if “they have lost their attractiveness,” ( since their partners cannot perform sexually.

Men with ED have problems with the chemical reactions that cause erections. Their arteries do not expand, the penis cannot fill with blood, and therefore does not become erect.  They may experience any three of the different levels of ED:

A total inability to achieve an erection

An irregular ability to achieve an erection

Brief erections -- an inability to maintain erections

How do you know if you are experiencing ED?

click hereIf you think that you are having a problem maintaining an erection during sexual activity and are interested in Viagra, talk with your healthcare provider.  Also try completing this quick self- screening questionnaire:


How does Viagra work?

Unlike previous treatments for ED (hormones, aphrodisiacs, etc.), Viagra affects the response to sexual stimulation.   No, it will not work immediately but when a man is sexually excited, Viagra alters the smooth muscle relaxant, which in turn releases nitric oxide, a chemical that is released in response to sexual stimulation. This muscle relaxation causes the penis to produce cyclic guanosine monophosphate (cGMP).  cGMP causes the arteries in the penis to relax and widen, allowing blood to flow. The arteries expand and harden and the veins that normally carry blood away from the penis become compressed.  The blood is not allowed to flow out of the penis but only in.  The penis enlarges and an erection results. After sexual intercourse, blood flows out of the penis and the erection goes away. (


Study on Viagra’s influence on psychological performance based on cGMP (

cGMP not only helps in the relaxation and widening of the penis, but it is one of the most important messengers in the Central Nervous System (CNS).   So important that small changes in the cGMP-level, an increase caused by Viagra, could easily alter the function of CNS.  Doctors believed that this affected the psychomotor skills of male patients and therefore developed a pilot study to test their hypothesis. They tested 6 healthy male volunteers with 7 different psychophysical performance tests. Each volunteer performed the test twice, once without the drug and once after a single oral dose of 100-mg Viagra.

The results of the experiment showed that only two parameters of 2 different tests showed significant differences.  The researchers concluded that Viagra showed no important impairment of psychophysical performance, however no strong improvement was found either.

Viagra’s Effectiveness

Viagra’s initial effectiveness was determined using a sexual function questionnaire.  Patients were asked to occasionally report how often they were able to maintain an erection during intercourse.   In addition, they were asked to keep diaries of their sexual history.  In all tested trials, men given Viagra had higher results than men on placebo drugs, plus the rates of success increased with the consumption of higher dosages. These findings were consistent, dependent on the severity of the patients erectile dysfunction. 

Although this method of research could contain certain experimental biases because of patient inaccuracies, Viagra has been proven to be successful in developing an erection about 75-80 percent of the time.  It has also been deemed successful thirty minutes after ingestion and effective for as long as four hours. (


Study shows that Viagra is most effective on patients with certain types of Erectile Dysfunction


A total of 141 patients between the ages of 27 and 78 years old were tested to determine the efficacy of Viagra based on their form of erectile dysfunction.  Each patient was started on 50 mg of Viagra and assessed monthly for 6 months. Patient’s erectile capacity changes were measured using the International Index of Erectile Capacity Form (IIEF). IIEF was tested on each follow-up visit and an additional 100 mg of Viagra was given to patients without a response to the medication.

Results showed that the average beginning IIEF score of 141 patients was 11.80 +/- 0.47 and by the end of 1 month the IIEF had increased to 20.70 +/- 0. The mean increase was 75.4%.  An initial positive response was recorded in 102 patients (72.3%) and 39 (27.7%) patients were unresponsive. In patients given an additional dosage of Viagra (100 mg), 17 patients were responsive.  After the overall treatment, 119 patients (84.4%) showed some response to Viagra.  This percentage is consistent with the overall claim made by Viagra manufactuers who stated that Viagra was effective about 80 percent of the time.

Next, a Penile Doppler ultrasonography displayed arterial insufficiency in 79 patients (56.03%), veno-occlusive dysfunction in 14 patients (9.93%), mixt vascular pathology in 14 patients (9.93%), and psychogenic dysfunction in 32 patients (22.7%). The researchers concluded that Viagra was most effective in those with arterial insufficiency and psychogenic types of erectile dysfunction.

Experimental Evidence         

Besides the mere experiments to test the effectiveness of Viagra, the numerous patient testimonials in support of its claims, serve as real life accounts of Viagra’s effectiveness. (

One woman accounted, after not being intimate with her husband for 22 years, that after he took Viagra “it was just like a honeymoon” ( all over again; in fact she cried.  Paulo Sant'Ana, a 58-year-old grandfather, took the pill and described his experience as "incessant, pleasurable." He claimed that it was so long-lasting that he stopped making love only when his partner begged for a rest.  ( Another man accounted that after taking Viagra, he experienced a tremendous change in his lifestyle.  He had energy and “float[ed] around the house as a result of it.” ( He also said that his experience was “like a guy who losses an arm and then somebody, by some stroke of some miracle, produces something that makes him have the arm to be useful to him again.” ( He claimed that Viagra helped him realize just what he was missing in life, and appreciate it more when he regained it.

Though many patient testimonials have been found in support of Viagra, no real scientific studies have been preformed looking at the emotional changes in mood or behavior.  More studies should be conducted to see what type of real impact Viagra has on men and their partners.

Precautions: Viagra is not for Everyone (

*Before taking Viagra inform your doctor if you have heart disease, a bleeding disorder, a stomach ulcer, or an eye disease.  Also talk to your doctor if you have sickle cell anemia, leukemia, or bone marrow tumors because these conditions can increase the risk of having an unwanted erection that can last up to 6 hours. 

         *This medication should not be given to women, children, or babies.

*You should not take Viagra if you are taking nitrate medicines such as nitroglycerin (Nitro-bid®, Nitro-Dur®, Transderm Nitro®, Nitrol ointment®, Nitrolingual Spray®) or isosorbide (Imdur®, Monoket®, Ismo®, Isordil®).  These medications may cause your blood pressure to drop to a very unsafe level.

*Viagra will not keep you or your partner from getting pregnant or protect you from sexually transmitted diseases.

Talk with your doctor before taking this medicine if you have an abnormally       formed or curved penis.

*Remember, Viagra is for men who have trouble getting and maintaining an erection. It is not for men who have normal sexual function.

Possible Side Effects

      *Heart Attack


      *Painful, Prolonged Erections


      *Irregular Heart Beats                                  

      *Impaired Vision



      * Urinary Tract Infections

Viagra’s Supporters

            Many different people and organizations rally in support of Viagra for a number of reasons.  For example many advocates for saving endangered species claim that “In Viagra [they] now have the potential to eliminate the demand for animal potency products.”( Since many Chinese-medicine practitioners’ recipes have always contained the use of endangered species, when there survival on earth was not a question, to increase sexual stamina, many now predict that East Asian markets may lose business to the new drug of choice for ED.    

Professor Edimar Bocci of Brazil’s Sao Paolo Heart Institute, is also a strong advocate for Viagra.  He presented a study at a cardiologist’s conference in Stockholm, in which he presented evidence that proved that Viagra increased heart patients overall physical health.  Although patients skipped heart medication in order to take Viagra and attain a more satisfying sex life, they remained healthy with the continued use of Viagra. ( 09/05- Viagra Can Give Heart Patients a Boost, Study Finds.)

Likewise in London, Scientists at the Hammersmith Hospital have done studies that have shown that Viagra helps people breathe easier at high altitudes, where oxygen levels are low.  Scientists at the National Center for Cardiology in Kyrgyzstan found that the same enzyme that constricts blood flow to the penis and prevents erections also produced breathlessness at high altitudes.  However when Viagra was administered, patients were able to breathe easier because Viagra blocked the action of the enzyme. (

Additionally, Viagra had gained international acclaim from numerous patients and media alike.  These supporters claim that Viagra is a life- changing, empowering, wonder drug, that has changed and will continue to change the health world forever.

            Though Viagra prescribers have been publicly ridiculed and humiliated, it “is [quickly] becoming the "designer" drug of the decade.”   ( Because of the revolutionary age in which we live, this new age medication has changed and will continue to change the lives of many individuals.  Because of Viagra many people are living joyful, satisfying lives.










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