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simply one paragraph or a few sentences. Taking one part of the answer out of context can lead to a misinterpretation of the intended message.
Paul Dillon speaks to thousands of students across Australia providing information on alcohol and drugs, particularly in relation to looking after
themselves and their friends. Some young people make contact with him to ask questions that they did not feel comfortable asking in front of their peers.
The Real Deal on Drugs allows young people to ask questions about drugs and provides them with access to accurate and up-to-date information.

Some of my friends have started using something called 'Special K'. It's a white powder and they snort it. What is it and what is the 'K hole' that they keep talking about?

'Special K' is a street term for ketamine, a powerful anaesthetic used in both human and veterinary surgery.  It is a dissociative drug, which means that when used, the mind leaves the body causing the user to experience quite intense hallucinations. Ketamine was first used extensively during the Vietnam War during battlefield surgery.  When soldiers returned home, those who had been given the drug talked about the experiences that they had had whilst under the effect of the drug and not surprisingly it started to be used recreationally. Its popularity increased quite dramatically in the 1990s, this time amongst the nightclub scene, with people reporting that the drug enhanced the clubbing experience (e.g., the music sounded different and the lights were more intense). 
Doctors and vets use ketamine in an injectable liquid form but 'Special K' users buy the drug in a fine crystal or powder form that is then snorted. Use too much of the drug and users can find themselves in a dissociated state, or as it is now called a 'k-hole'.  As a result, smaller, measured doses (called 'bumps') are taken, increasing the chance of having a more 'pleasurable' experience with the drug. So what exactly is a 'k-hole' and is it dangerous?
A 'k-hole' is difficult to define as it appears to mean different things to different people, but essentially there appears to be two types of 'k-holes'. Some users regard it as the state of dissociation (i.e., when your mind leaves your body) and in these cases it is definitely regarded as a 'positive' experience. Often the initial events may feel like they are happening at a high speed, with people reporting feeling as though they are zooming through tunnels or computer networks, traveling on rollercoasters or being swept through a sewer. However, there is another place you can go when you have one 'bump' too many – a black place which many users believe they will never return from. Some compare this to a 'near-death experience' (NDE) and see it as a dark and frightening place and somewhere that they never want to go to again! There is a real sense that what is being experienced is real and that one is actually dead or dying, and that what is happening is inexpressible in words.
We really don't know very much about the long-term use of ketamine as most of the research conducted in the area has been looking at its use by medical professionals for surgery. There is certainly growing evidence that regular use of ketamine can cause serious bladder and urinary tract problems. This can lead to difficulty urinating and there have now been documented cases of regular users of 'Special K' needing to have surgery in an attempt to fix these problems. It also needs to be remembered that the potential for ketamine users to do harm to themselves while in the 'k-hole' is great and there are many stories of users burning or cutting themselves unknowingly whilst using the drug.