I am very curious regarding anyone's experience with long term use of ketamine. It seems that a significant amount of contradictory data exists on this subject. Some of the most notable ketamine proponents (John Lilly, Marica Moore, DM Turner) seemed to have suffered severe personality shifts to say the least, (Turner drowned in his bathtub on K and Moore froze to death after a massive overdose/suicide). The only study I am aware of documenting ketamines pharmacological danger is Olney's writings on his now infamous lesions. Apparently everyone is eager to dismiss these findings in human scenarios but I believe they are still relevant. What compounds the issue is that several substances have been found to prevent Olney's lesions (LSD, barbs) but little to no information is available on the dosages and modalities. I am reading Karl Jansen's excellent book Ketamine Dreams and Realities but it seems Jansen like most ketamine proponents is so enamored with the substance that he tends to dismiss it potential long term damage. One aspect that is certainly relevant is the permanent tolerance that many report after repeated ketamine use. Even after abstaining from use for a year or more, upon next use it can still be difficult or impossible to induce a full fledged k-hole experience even with massive doses. Clearly some permanent physiological change is taking place. It seems ketamine deserves some harm reduction discussion/research on the level that MDMA has received in the past couple of years. One close individual has become an absolute kook after continual rampant abuse. Any input from long term ketamine users or researchers is much appreciated.