Hearing Issues Levitra and other PDE5 inhibitors have been linked to hearing issues, including some cases of sudden hearing loss. Stendra avanafil : This is an as-needed medication taken 30 minutes before sex and can last up to six hours. Priapism is a serious medical issue, meaning that if you get an erection that lasts for four hours or longer after using Levitra, you should seek medical assistance immediately. Sildenafil was approved by the FDA to treat erectile dysfunction back in , making it the oldest of the three most widely used ED medications used today. Drug Design, Development and Therapy.A new drug application (NDA) for vardenafil was submitted to the FDA in September The other new PDE5 inhibitor is tadalafil. It has a unique chemical structure and a pharmacokinetic and pharmacodynamic profile that differs from both sildenafil and vardenafil. The manufacturer of tadalafil submitted an NDA for it in June  · Erectile dysfunction, or ED, affects approximately 30 million men in the United States, making it one of the most common forms of sexual dysfunction in men.. Luckily, ED is no longer an impossible condition to treat. Today, a wide range of medications are available to treat erectile dysfunction and improve sexual performance in men. 5 rows · The basic cost of Levitra is approximately: Brand name: $ to $1, for ten to thirty 10 mg.