Erectile dysfunction (ED) medications are treatments use to help men who have difficulty achieving or maintaining an erection suitable for sexual activity. Common prescription treatments include phosphodiesterase type 5 (PDE5) inhibitors such as sildenafil, tadalafil, vardenafil, and avanafil. This medicine work by increasing blood flow to the penis in response to sexual stimulation. Treatment choice depends on the underlying cause of ED, overall health, medical history, and other medicines that you take.