Sexual Dysfunction Drugs Linked to Vision Loss
WASHINGTON, D.C. – The U.S. Food and Drug Administration (FDA) should immediately require a black box warning for doctors and patients about the potential for the popular erectile dysfunction drugs, including the popular drugs Viagra (sildenafil), Cialis (tadalafil) and Levitra (vardenafil) to cause possible irreversible vision loss, Public Citizen said today.
In a petition filed with the FDA, Public Citizen noted that Viagra accounts for more cases of a type of vision loss called ischemic optic neuropathy (ION) than any other drug (19 percent) and more than double the percentage of the next most often-reported drug. Public Citizen obtained these results by analyzing data from the FDA’s Adverse Event Reports database.
Public Citizen found that the number of case reports of ION per million prescriptions was 18-fold higher for patients taking Viagra and 25 times higher for Cialis compared to patients taking Lipitor, another drug used by people with similar cardiovascular risk factors. Many case reports document that vision loss has occurred in close association with the use of these erectile dysfunction drugs, and several reports show that the patients with temporary vision loss experienced such loss again upon re-exposure to the drug. Despite this, the current FDA-approved labeling for the drugs states that, “It is not possible to determine whether these events are related directly to the use of PDE5 inhibitors,” implying that the drugs do not cause blindness.
In addition to 50 cases of ION reported to the FDA for these drugs, 60 other cases of related conditions such as blindness, blindness unilateral visual field defect, scotoma, or optic nerve infarction have been reported in patients taking these three drugs.
The FDA should add a “black box” warning to the professional package insert – a warning that is in bold type and surrounded by a black box to make it stand out. The petition is co-filed with Dr. Howard D. Pomeranz, the first ophthalmologist to publish studies linking these drugs to blindness.
The agency should establish a registry of patients who take the drugs and develop vision loss, the petition says. Drug companies should be required to send “Dear Doctor” letters to all U.S. physicians about the signs and symptoms of vision loss associated with the erectile dysfunction drugs.
The FDA should require that an FDA-approved Medication Guide include the black box warning and be written in non-technical language and be distributed to patients with each new and refill prescription for the drugs informing them of the risk of vision loss.
“The current Patient Information Leaflets are provided by private companies, not the FDA, and contain no clear warnings, lump serious and less serious adverse events together, and bury information in large amounts of other material” says the petition. The petition also states that the sections of the leaflets describing the potential risk “have neither titles nor bolding to call attention to this serious adverse event; instead, everything imaginable has been done to detract from its relevance and prominence.”
“It is the Food and Drug Administration’s job to immediately and coherently tell consumers about the risks associated with the drugs they put into their bodies,” said Dr. Sidney Wolfe, director of Public Citizen’s Health Research Group and co-author of the petition. “The agency has once again failed in this responsibility. “These drugs need much stronger warnings, especially a black box warning such as the one we have proposed.”