Viagra May Cause Blindness: Are You at Risk
The
anti-impotence drug Viagra increases the risk of blindness,
according to the latest research, which identifies
around 14 men who developed vision problems after
taking the drug. The FDA has also reported that it
has received around 50 complaints from men saying
that there vision has been affected by Viagra. Doctors
now believe that Viagra is linked to a condition known
as NAION or as non arteritic anterior ischemic optic
neuropathy, which causes a rapid loss of vision and
can in serious cases lead to permanent blindness,
as the optic nerves get inflamed and swollen.
However according to Pfizer Inc, the manufacturer
of Viagra, these cases are just as coincidences as
Viagra has been used by over 20 million men in the
last seven years and only 50 cases of blindness have
been reported. Pfizer is nevertheless in talks with
the FDA to consider revising its prescription label
for Viagra to mention that in rare cases this drug
does cause blindness in men. It is also important
to keep in mind that men who take Viagra do experience
temporary color changes in their vision with objects
having a bluish tinge to them or their vision becomes
blurred.
As such the risk for taking Viagra is uncertain as
no conclusive evidence has been brought forward to
clearly define whether Viagra actually causes blindness
or not. Pfizer, while defending the safety of its
drug stated that in a review of 103 Viagra clinical
trials involving over 13,000 patients, no reports
of non-arteritic anterior ischemic optic neuropathy
were found. The company goes on to say that there
is no proof showing that NAION occurs more frequently
in men taking Viagra than men of similar age and health
who did not take the drug. With the FDA currently
investigating Viagra and other anti-impotence drugs
and their connection with NAION, many people in the
medical community are skeptical about the connection
between Viagra and blindness.
The concern about Viagra and NAION was initially
brought up by a neuro-ophthalmologist at the University
of Minnesota, Howard Pomeranz who appears to be the
first doctor to have made a connection between Viagra
and blindness in one of his patients in 1998. This
doctor believes that Viagra which alters the flow
of blood in key parts of the body could also have
an affect on blood circulation to the optic nerve.
Those at risk for developing NAION, already have
bad eyesight or have diabetes, hypertension or high
cholesterol as well. Though none of these systematic
disorders are associated with this eye disease, they
still play an important role in causing NAION. While
the exact natural history of NAION is not known, and
a definite casual relationship cannot be established
between this disease and Viagra, caution should be
exercised while taking this drug. Viagra is a prescription
medication and should be taken only under the advice
of your doctor. Do not take Viagra for any other purpose
than for the treatment of erectile dysfunction.
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