Priapism Priapism is a type of painful, prolonged erection that lasts for four hours or longer. An estimated 0. The difference between the vardenafil molecule and sildenafil citrate is a nitrogen atom’s position and the change of sildenafil’s piperazine ring methyl group to an ethyl group. Common and temporary side effects of vardenafil include headaches, flushing, nasal congestion, indigestion and heartburn, nausea, dizziness, visual disturbances and reduced blood pressure. It also has some side effects you should be aware of before you start using it. If you experience any loss of vision after using Levitra, excluding the transient color vision issue listed above, you should seek medical attention immediately. When erectile dysfunction is psychological , options such as therapy or making certain changes to your habits may help you to stay hard without medication.Vardenafil 4 tablets Blister 20 mg. Vardenafil, sold under the brand name Levitra among others, is a medication that is used for treating erectile dysfunction. As of , the co-promotion rights of GSK on Levitra have been returned to Bayer in many markets outside the US. In Italy, Bayer sells vardenafil as Levitra and GSK sells it as Vivanza. This might allow for more spontaneity. For those who are taking tadalafil (Cialis) as needed, it’s taken 30 minutes before sexual activity. As a comparison, vardenafil is taken 60 minutes before sex. Another difference is that tadalafil (Cialis) is only available as a tablet, whereas vardenafil is available as a tablet and an ODT. Generic Levitra Availability. Last updated on Levitra is a brand name of vardenafil, approved by the FDA in the following formulation(s): LEVITRA .