One of my favorite lines/samples in an EDM track 'ketamine, snorted by humans but used by vets to anesthetize animals'. I believe was taken from a 20 / 20 episode on raves. Well actually the whole bit of samples they used was pretty fun for the track. Think that line was Barbra Walters.
Don't do regular doses of ketamine. If you do it once and stay the fuck away from the internet for two weeks, that's fine. If you do it in supervised therapy sessions thats fine.