Some cobras can spit their venom into a victim's eyes, causing extreme pain and blindness.
However, the most common and well known method of venom delivery is injection into a victim's body through their bite. You will need the QuickTime Plug-in to view this movie. An elapid's venom contains postsynaptic neurotoxins that spread rapidly in its victim's bloodstream, causing respiratory failure and, eventually, death. It binds to the receptor sites, blocking them from interacting with acetylcholine molecules. Even worse, the venom molecule will not immediately break down and vacate the receptor site, effectively removing the site from active duty.