Featured Research

from universities, journals, and other organizations

FDA Approves Impotence Pill, Viagra

Date:
April 1, 1998
Source:
Food And Drug Administration
Summary:
The Food and Drug Administration has announced the approval of Viagra (sildenafil citrate), the first oral pill to treat impotence, a dysfunction that affects millions of men in the United States.

March 27, 1998 -- The Food and Drug Administration today announced theapproval of Viagra (sildenafil citrate), the first oral pill totreat impotence, a dysfunction that affects millions of men inthe United States.

Unlike previously approved treatments for impotence, Viagradoes not directly cause penile erections, but affects theresponse to sexual stimulation. The drug acts by enhancing thesmooth muscle relaxant effects of nitric oxide, a chemical thatis normally released in response to sexual stimulation. Thissmooth muscle relaxation allows increased blood flow into certainareas of the penis leading to an erection.

Viagra was evaluated in numerous randomized, placebocontrolled trials involving more than 3000 men with varyingdegrees of impotence associated with diabetes, spinal cordinjury, history of prostate surgery, and no identifiable organiccause of impotence. Patients also had a wide range of otherconcomitant illnesses including hypertension and coronary arterydisease.

The drug's effectiveness was assessed primarily using a sexual function questionnaire. Patients were asked to report atthe beginning, and periodically throughout the studies, how oftenthey were able to achieve an erection adequate for intercourse, and how often that erection was maintained after penetration. Inaddition, patients kept diaries of their sexual histories. Inall trials, men on Viagra reported success more often than didmen on placebo, and rates of success increased with dose. Thefindings were consistent in men representing a wide range ofseverity and etiology of their erectile dysfunction (impotence). Men with diabetes or radical prostate surgery had somewhat lessimprovement than did other groups.

The recommended dose is 50mg taken one hour before sexualactivity; individuals may need more (100mg) or less (25 mg) and dosing should be determined by a physician depending oneffectiveness and side effects. The drug should not be used morethan once a day.

The most common side effects reported in clinical trialsincluded headache, flushing, and indigestion, which occurred at aslightly higher rate in patients taking the drug than among thosetaking placebo. Some patients on Viagra (about 3 percent) alsoreported changes in vision, principally altered colorperception.

The drug should not be used with organic nitrates such asnitroglycerin patches or sublingual tablets because thecombination may lower blood pressure. The safety and efficacy of using Viagra with other treatments for impotence has not beenstudied, and the use of such combinations is not recommended.

Viagra confers no resistance to AIDS or other sexuallytransmitted diseases.

Before taking Viagra, patients are advised to:

  • Have a thorough medical history and physical examination todiagnose impotence, determine underlying causes and identifyappropriate treatment, and
  • discuss the cardiac risk associated with sexual activityprior to initiating any treatment for impotence.
Viagra is manufactured by Pfizer Pharmaceuticals, New York, NY. The product was approved by FDA in less than sixmonths after submission. The FDA's clinical review of thestudies, approval letter and labeling can be found on theinternet at http://www.fda.gov/cder/news/viagra.htm.


Story Source:

The above story is based on materials provided by Food And Drug Administration. Note: Materials may be edited for content and length.


Cite This Page:

Food And Drug Administration. "FDA Approves Impotence Pill, Viagra." ScienceDaily. ScienceDaily, 1 April 1998. <www.sciencedaily.com/releases/1998/04/980401074901.htm>.
Food And Drug Administration. (1998, April 1). FDA Approves Impotence Pill, Viagra. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/1998/04/980401074901.htm
Food And Drug Administration. "FDA Approves Impotence Pill, Viagra." ScienceDaily. www.sciencedaily.com/releases/1998/04/980401074901.htm (accessed July 31, 2014).

Share This




More Health & Medicine News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

House Republicans Vote to Sue Obama Over Healthcare Law

House Republicans Vote to Sue Obama Over Healthcare Law

Reuters - US Online Video (July 31, 2014) The Republican-led House of Representatives votes to sue President Obama, accusing him of overstepping his executive authority in making changes to the Affordable Care Act. Mana Rabiee reports. Video provided by Reuters
Powered by NewsLook.com
Despite Health Questions, E-Cigs Are Beneficial: Study

Despite Health Questions, E-Cigs Are Beneficial: Study

Newsy (July 31, 2014) Citing 81 previous studies, new research out of London suggests the benefits of smoking e-cigarettes instead of regular ones outweighs the risks. Video provided by Newsy
Powered by NewsLook.com
Dangerous Bacteria Kills One in Florida

Dangerous Bacteria Kills One in Florida

AP (July 31, 2014) Sarasota County, Florida health officials have issued a warning against eating raw oysters and exposing open wounds to coastal and inland waters after a dangerous bacteria killed one person and made another sick. (July 31) Video provided by AP
Powered by NewsLook.com
Health Insurers' Profits Slide

Health Insurers' Profits Slide

Reuters - Business Video Online (July 30, 2014) Obamacare-related costs were said to be behind the profit plunge at Wellpoint and Humana, but Wellpoint sees the new exchanges boosting its earnings for the full year. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins