Erectile dysfunction drugs ‘pose no threat to vision’April 14th, 2009 - 11:37 am ICT by ANI
Washington, Apr 14 (ANI): Erectile dysfunction (ED) drugs like Viagra and sildenafil pose no threat to vision, say researchers.
According to a report in the April issue of Archives of Ophthalmology, one of the JAMA/Archives journals, two medications used to treat the disorder in men do not appear to have visual side effects when taken daily for six months, despite concerns about eye-related complications.
The advent of the medications sildenafil citrate (sold as Viagra), tadalafil (sold as Cialis) and verdenafil hydrochloride (sold as Levitra) has profoundly changed the treatment of erectile dysfunction.
These medications are known as selective phodiesterase type 5 (PDE5) inhibitors because they treat erectile dysfunction by interfering with the action of the compound PDE5 on the blood vessels in the penis. However, PDE5 inhibitors may also act on similar compounds in the retina, the part of the eye that receives and transmits images.
Mild and transient blurred vision, blue-tinged vision and altered light perception have been reported by men taking these drugs, and some visual complications of long-term use have been suggested.
To reach the conclusion, William H. Cordell, M.D., of Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, and colleagues conducted a randomized placebo-controlled study to assess changes in the retina among men taking tadalafil or sildenafil.
A total of 244 healthy men, some with mild erectile dysfunction, age 30 to 65 were recruited. Of these, 85 were randomly assigned to take 5 milligrams of tadalafil, 77 to take 50 milligrams of sildenafil and 82 to take a placebo daily for six months.
The men underwent comprehensive ophthalmologic examinations including electroretinography (a test to measure the electrical response of the light-sensitive rods and cones in the eye, used to detect diseases of the retina) before, during and after treatment.
Among the 194 men (79.5 percent) who completed the study, no significant differences were found between treatment and placebo groups on electroretinography, visual function tests, measurements of intraocular pressure (pressure within the eyeball) or assessments of the anatomy of the eye.
Nine participants (two in the placebo group, one in the tadalafil group and six in the sildenafil group) discontinued the study because of an adverse event, but only one of those was an ophthalmologic event (in the placebo group). No abnormalities that would be suggestive of drug toxicity were observed in any of the participants.
“There are several reasons ophthalmologists need to be acquainted with the pharmacologic profiles of PDE5 inhibitors and their potential side effects,” the authors write.
“The frequency of erectile dysfunction, which is a form of peripheral vascular disease that impairs men’s abilities to achieve and maintain an erection, increases dramatically with age and in the presence of cardiovascular risk factors. Therefore, many men who take PDE5 inhibitors to treat their erectile dysfunction will also be followed up by ophthalmologists for ocular disorders such as diabetic retinopathy, macular degeneration and ocular vascular disease,” they added.
“Furthermore, PDE5 inhibitors can exert direct effects on the retina, and such effects probably account for many of the visual side effects such as blue-tinged vision and light sensitivity that have been reported,” they conclude.
However, “our results indicate that there is no cumulative damage or effect of clinical significance for either 5 milligrams of tadalafil or 50 milligrams of sildenafil taken daily for six months,” they said. (ANI)
- Viagra may blur vision for a while, but doesn't blind you - Apr 14, 2009
- Viagra has no harmful effect on men's vision - May 18, 2009
- Viagra may cause hearing loss - May 19, 2010
- Topical cream for erectile dysfunction could prove safer - Sep 19, 2009
- Nano drug delivery helpful in treating erectile dysfunction - Sep 19, 2009
- Jury still out on Viagra, Levitra and Cialis championship race title - May 19, 2009
- Men can do well with ginseng, saffron - Mar 28, 2011
- Products to enhance men's sexual performance recalled in NZ - Sep 24, 2010
- Male sexual dysfunction drugs may some day help women also - Apr 17, 2009
- Erectile dysfunction drug could help treat bladder outlet symptoms - Apr 27, 2009
- Argentine province to produce Viagra for free distribution - Mar 23, 2012
- 'Nothing natural about 'Natural Viagra' being sold online' - May 03, 2011
- Erectile dysfunction drug could enhance delivery of herceptin to brain tumours - May 08, 2010
- Wanna 'spice' up your sex life? Add these natural enhancers in diet - Mar 28, 2011
- Popular drugs could trip sex drive - Mar 08, 2011
Tags: blood vessels, blurred vision, cialis, cordell, electrical response, eli lilly, eli lilly and company, hydrochloride, jama, levitra, light perception, lilly and company, lilly research laboratories, milligrams, ophthalmology, pde5 inhibitors, placebo, retina, rods and cones, tadalafil