Defense Threat Reduction Agency. When DTRA employees arrive at work every morning, they are addressing the number one national security threat we face as a nation. The threat of WMD is a threat that can change everything about the way in which Americans live their lives. Our mission at the Defense Threat Reduction Agency (DTRA) â to safeguard the United States and its allies from weapons of mass destruction â is of paramount importance for the defense of our country.
Levitra is the brand name for vardenafil, an oral medication used to treat men who have sexual impotence, also known as erectile dysfunction or ED.It's part of a group of drugs known as phosphodiesterase-5 (PDE5) inhibitors.evitra increases venous congestion in that area and helps a man get and keep an erection during sexual intercourse. By itself, Levitra does not cause an erection-there must also be physical stimulation of the penis to achieve an erection.
With Levitra, the effects last for about 5 hours. With Viagra, the effects last approximately 4 hours. Cialis works a bit faster (within about 15 minutes), and the effects last much longer -- up to 36 hours in some cases.Stendra can start working in as little as 15 minutes and last up to 6 hours.. A. There are only five oral drugs approved by the FDA to treat erectile dysfunction: tadalafil (Cialis), vardenafil (Levitra, Staxyn), avanafil (Stendra), and sildenafil (Viagra). All work by increasing the flow of blood into the penis so that when a man is sexually stimulated, he can get an erection.