Parker & Waichman, LLP Attorneys at Law Viagra Information Guide
The Case Against Viagra:
In a recent study, US researchers describe seven patients who developed nonarteritic ischemic optic neuropathy (NAION), an eye
ailment that can result in permanent vision loss, after taking Viagra
(sildenafil) for erection difficulties. Combined with past reports, this
Manufacturer:
study brings the total number of sildenafil-related NAION cases to 14.
"For years, we've known that a number of men who take Viagra will
Generic Name:
experience short-term color changes in their vision and see things as
green or blue," study co-author Dr. Howard D. Pomeranz, from the
University of Minnesota in Minneapolis, said in a statement. With the
Date Approved:
exception of one patient whose symptoms began 24 to 36 hours after
using Viagra, the patients developed symptoms within 24 hours of
In all patients, the initial symptoms were blurred vision and some
degree of vision loss. In one patient, both eyes were affected, whereas in the remainder, just one was involved. Three patients had
Approved Uses:
preexisting eye problems that may have increased their risk of
Viagra News May 27, 2005 Serious Side Effects: Serious Side Effects
Pfizer Inc., the world's largest drug maker, said U.S. regulators may
require a label warning that the Viagra impotence drug has been
linked to reports of blindness and vision loss in at least one in a
The FDA has 38 reports of the blindness, among users of Viagra.
Related Topics
Pfizer spokesman Daniel Watts confirmed Friday that the drug maker
was in discussions with the FDA about adding a disclosure to
Viagra's label to say that in rare cases, men taking Viagra had
The government in 1998 approved Viagra. It may aid in the treatment
of enlarged hearts that can result from high blood pressure, tests on animals indicate.
If you or a loved one has been injured by Viagra, Parker & Waichman, LLP will evaluate your case for free.
Viagra (Sildenafil)
Sildenafil citrate, sold under the ) Caverta, is a . Viagra pills, intended to treat impotence, are blue with the words "Pfizer" on one side and "VGR xx" (with xx representing 25, 50 or 100, the dose of that pill in milligrams) on the other.
Sildenafil, initially known as compound UK- (a form of suggested that the drug had little effect on angina, but that . Pfizer therefore decided to market it for erectile dysf in , becoming the first pill approved to treat erectile dysfunction in the United States, and offered for sale in the United States later that year. It soon became a great success: annual sales of Viagra in the period .
The name "Viagra", like many drug names, is a marketing invention. It was possibly inspired word "vyāghra", which means "tiger". The word rhymes with "Niagara" (d Niagara, being such an impressive cataract, evokes a sense of incredible erectile and ejaculatory strength). The sound of the word also suggests the words "vigor" and "virile".
Even though Viagra is only available by prescription from a doctor, it was advertised directly ). Numerous sites on the Internet offer Viagra for sale after an "online consultation," a mere web questionnaire. The "Viagra" now call themselves "herbal Viagra" or are presented as blue tablets imitating the shape and colour of Pfizer's product. A , has become popular among rave partygoers. Viagra is also informally known as "Vitamin V", "the Blue Pill", and goes by various other nicknames.
It has been suggested that Viagra would lead to a marked drop in the demand for certain horns and that the drug may . 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 properties, it is unclear that the natural remedies would compete with this new clinical drug.
Pfizer's worldwide patents on sildenafil citrate will expire in 2011–2013. The (see below) as treatment of impotence has been invalidated in 2000 because of obviousness; this decision was upheld on appeal in 2002.
Mechanism of action
Part of the physiological process of erection involv (NO) in the which results in relaxation in the corpus cavernosum, resulting in increased inflow of blood and an erection.
Sildenafil is a potent and selectiv(PDE5) which is responsible for degradation of cGMP. 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, sildenafil should not cause an erection. Other drugs that operate by the same mechanism (Cialis®) and (Levitra®).
Sildenafil is and excret. If taken with a high fat meal, there may be a delay in absorption of Viagra and the net effect might be muted slightly as the plasma concentration will be lowered.
Some reports have claimed that sildenafil causes enhanced sexual pleasure for women by increasing blood flow to the sexual organs.
Dosage and price
As with all , proper dosage is at the discrThe dose of sildenafil is 25 mg to 100 mg taken once per day between 0.5 to 4 hours before .
It is usually recommended to start with a dosage of 50 mg and then lower or raise the dosage as appropriate. The drug is sold in three dosages (25, 50, and 100 mg), all three costing about USD$10 per pill. 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.
Contraindications and side effects
• When taking other nitric oxide donors,
("poppers") (Cheitlin et al 1999)
• is inadvisable due to cardiovascular risk factors • Severe (decreased liver function) • • (low blood pressure) • Recent • (including genetic disorders of retinal
Amongst sildenafil's serious adverse effects are: .
Common side effects include sneezing, headache, flushing, dyspepsia, prolonged erections, palpitations and photophobia. Visual changes including blurring of vision and a curious bluish tinge have also been reported.
found that sildenafil could lead to vision impairment. An investigation is currently underway. Some patients developed (NAION), an eye problem that can result in permanent vision loss. Combined with past reports, this study brings the total number of sildenafil-related NAION cases to 14.
. It appears that described as a "cup" in the retina that is the constant among all cases.
Uses outside of erectile dysfunction Pulmonary hypertension
Studies have shown that apart from in erectile dysfunction, sildenafil citrate is also effective in (PAH). It appears to relax the arterial wall, decreasing the pressure on the lung vasculature and improving symptoms of right-sided heart failure. As a result of these studies, Pfizer submitted an additional registration for sildenafil . Presumably to avoid confusion with Viagra, the preparation is named Revatio and the 20 milligram tablets are as therapies for this condition.
Raynaud's phenomenon
In 2005, Dr. Roland Fries and colleagues reported that sildenafil cut the frequency of
attacks, reduced their duration by roughly one half, and more than quadrupled the mean capillary blood velocity. This was a double-blind, placebo-controlled crossover trial and the patients had both the primary and secondary forms and had all discontinued the more conventional treatments for this (Fries et al 2005). It had earlier been reported to be effective for Raynaud's in a 65-year-old woman with pulmonary hypotension (Rosenkranz et al 2003); (Rosenkranz et al 2004), and in nine women and one man treated by a Dr. Jack R. Lichtenstein of Annapolis, Maryland over a three-year period (Lichtenstein 2003).
If you or a loved one has been injured by Viagra, Parker & Waichman, LLP will evaluate your case for free.
ASTELLAS PHARMA Ges.m.b.H BASISPRESSEMAPPE 2013 ASTELLAS PHARMA INC. Das weltweite Unternehmen Das weltweit tätige Pharmaunternehmen Astellas Pharma Inc. ist im April 2005 aus einer Fusion der beiden japanischen Firmen Fujisawa und Yamanouchi entstanden. Zahlen und Fakten Heute steht Astellas Pharma Inc. unter den Top 25 der Phar-ma-Rangliste und beschäftigt weltwe
PICA Drug List - Alphabetial Listing Key: MAND. MAIL = the indicated medication must be ordered through CFI Mail Order. STP = the indicated medication is subject to the Step Therapy Program:use 1st line agents (or generics) first FER = the indicated medication is indicated for the treatment of infertility. SPBM = the indicated medication is only available through CuraScript after on