Understanding Viagra Black and Its Active Ingredients

Cup-to-disc ratio and its role in pathogenesis.

[13] Bollinger K, Lee MS.

Which drug was approved first?

* visual field defect, blindness, blindness unilateral, scotoma, or optic nerve infarction Patient information leaflets are provided by private companies, not the FDA, and so are not regulated. Some of the current patient information leaflets contain no clear warnings, lump serious and less serious adverse events together, and bury information in large amounts of other material. Readability varies greatly, with small font-sizes and single-spacing being common (see Attachment). Two general types of risk factors for NAION have been studied: disease/lifestyle factors and those relating to the anatomy around the optic disc. Although definitive data are lacking, certain factors appear to predispose individuals to NAION.

Serious side effects (seek emergency care)

It has been implied, both from studies and anecdotal data that pre-existing hypertension, diabetes, elevated cholesterol, and/or an arteriosclerotic risk profile put patients at risk. [6],[7] However, people taking Lipitor and Zocor fall into a group likely to have these risk factors, yet we find a much lower percentage of cases of ION with Lipitor and Zocor (Table 1). Diabetes emerged as a risk factor in two studies undertaken before Viagra approval. One case-control study looked at diabetes, hypertension, high cholesterol, coronary artery disease, tobacco use, and body mass index as risk factors for NAION and found that only diabetes was statistically significant. [8] In a larger study (n=326 cases) of people each of whom already had NAION in one eye and was being followed to determine risk factors for NAION in the unaffected eye, 15% developed NAION in the other eye over a 5 year period. Recurrent visual field defect and ischemic

optic neuropathy associated with tadalafil rechallenge.

Related questions

Because reports to the FDA’s AERS database may not have used the same preferred terms to describe ION, we used six search terms recommended by neuro-ophthalmologist Dr. Jonathan Trobe at the University of Michigan Medical School: ischemic optic neuropathy (ION), visual field defect, blindness, blindness unilateral, scotoma, or optic nerve infarction. We broke the results into two parts: the reporting rate for ION and that of the other five terms (non-ION). A patient could have ≥1 of these terms. We tabulated the number of cases of ION for the three PDE5 inhibitors as well as for two statin drugs, since the statins would be given to a similar group of people, i.e., older men more likely to have heart disease and/or diabetes.

Media Inquiries

By dividing the number of cases by the total number of prescriptions filled, we were able to estimate the ION reporting rate for each drug (Table 3). The rate of ION with Viagra was 18 times higher than that with Lipitor, the largest-selling statin drug; Cialis was 25 times higher, but the number of Cialis cases in the database, thus far, is small. Even though the number of cases of ION is still very small with Cialis, the numbers of prescriptions is very low compared with Viagra (Cialis was approved in November 2003, Levitra in August 2003, and Viagra in March 1998). It is clear, however, looking at the vision-related non-ION terms, that all of these drugs clearly have an adverse effect on the eye. It could be that there were many more cases of ION not reported to the FDA as such, since the numbers of non-ION cases (corrected for the number of prescriptions) are an order of magnitude higher with all three PDE5 inhibitors compared with the two statins.