Sanofi and Eli Lilly and Company plans to seek approval to sell the erectile dysfunction (ED) drug Cialis (tadalafil) over the counter in the United States, Europe, Canada, and Australia. The plan would require approval from regional regulatory agencies, such as the U.S. Food and Drug Administration. Pfizer previously sought OTC approval for its ED medication, Viagra (sildenafil citrate), but withdrew the application in 2008 after the European Medicines Agency expressed concerns over the drug’s safety.

Concerns about OTC availability of ED drugs stem from both their potential interaction with other medications—these drugs should not be taken in conjunction with nitrates—and their potential for abuse. One study found that more than 20 percent of men aged 18 to 30 years had taken ED medications for recreational use. Recreational use of ED medications was also associated with alcohol and illicit drug abuse, as well as risky sexual behavior.

Rather than obtaining a prescription from their physician, many men turn to “natural” supplements that claim to treat ED and are widely available online. However, a 2009 FDA report found that many of these supplements contain prescription medications and have the potential to interact with other medications. “The number of these problematic products available on the Internet appears to be increasing,” said Michael Levy, director of the FDA’s Division of New Drugs and Labeling Compliance.