Men who suffer from erectile dysfunction often turn to Viagra to
solve their problem. While it has been known for years that some
men taking this impotence drug will experience short-term blue/green
color blindness, headaches and flushing, a much more serious side
effect has been revealed: A team of ophthalmologists has identified
a condition that caused permanent blindness in a group of males
who had taken Viagra.
The condition? Nonarteritic ischemic optic neuropathy (NAION).
It is depicted as "stroke of the eye" and takes place
when the blood flow is cut off to the optic nerve, injuring the
nerve and causing permanent vision loss.
Proof Viagra Causes NAION
Ophthalmologists identified seven patients (ages 50-69) who had
distinctive NAION features within 36 hours of taking Viagra; six
patients had vision loss within a mere 24 hours after use of the
drug. Moreover, all of the patients had at least one of the following
arteriosclerotic risk factors:
- Diabetes
- Hypertension
- Hyperlipidemia: excess fat or lipids in the blood
- Hypercholesterolemia: elevated cholesterol
... as well as a low cup to disk ratio--a way doctors measure
the small circular indentation where the optic nerve binds to the
eyeball--meaning the blood vessels and nerves are tightly bundled
together in the small space behind the eye. And due to the fact
that Viagra regulates a chemical to constrict the body's arteries,
this could cut off blood flow to the optic nerve, particularly in
those who suffer from low cup to disk ratio, where blood vessels
and nerves are already tightly packed, and cause vision loss.
Journal
of Neuro-Ophthalmology March 2005, Vol. 25, Issue 1: 9-13
PharmaLive.com
March 31, 2005
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