Is a dissociative anesthetic (the mind dissociates from the body, and pain). May cause tachycarddia, increased secretions, diplopia, myoclonus, HTN or hypotension, hallucinations, out of body and/or near death experiences, and many other side effects. Should be avoided in patient with history of psychosis. May be used as an adjuvant to regularly scheduled and breakthrough pain meds. All of the above and more, so read up!