AKA: K, Special K, vitamin K

K is an anaesthetic and is sometimes referred to as ‘horse tranquiliser’. It’s one of the chems used in dance clubs or during sex.

Ketamine can come as a powder or a liquid that’s dried to make the powder.

How it’s used

As a powder, K can be snorted, which is known as a bump, or added to drinks.

K should never be mixed with alcohol or GBL as the drugs can greatly amplify the effects of one another.

K can be smoked if the powder’s mixed in a joint with cannabis and tobacco. Ketamine powder can also be mixed with water and injected into a muscle, but never a vein. The powder can also be snorted or sprayed up the nose. K can also come as a pill.

Highs and lows of ketamine

Ketamine can boost energy levels in small doses or make users feel high, numb, cut off from their body or in a dreamy, floating state.

K can cause hallucinations and an out-of-body experience that can feel like the user is entering a different reality, meeting God or aliens.

The effects last 45-90 minutes if snorted, and up to three hours if injected or swallowed.

The side effects of K can include:

  • dizziness
  • feeling sick and throwing up, which is risky as the user might choke on their vomit if they’ve passed out
  • feeling disorientated and detached from reality
  • racing heartbeat and shallow breath
  • blurred sight and speech
  • bladder dysfunction – in extreme cases even peeing ‘jelly’
  • urinary tract infections like cystitis
  • waking up with bruises and injuries – K numbs the body, so it’s easy for users to injure themselves without feeling pain.
  • A large enough dose can cut people off from their surroundings and sense of self. This is called a ‘K hole’ and can last for up to 90 minutes. Users might find it hard or impossible to move or talk in this state and swallowing or breathing can be difficult.

Sex on ketamine

Although ketamine can make users feel horny, it can make it difficult to get a hard-on or cum.

K can be used by guys who are into getting fisted as it relaxes the arse muscles.

As the drug makes people feel pain less, rough sex can lead to damage inside a users arse or cuts and bleeding that aren’t noticed. This may mean more risk of HIV, hepatitis C and other infections being passed on.

Ketamine can lower inhibitions, which might lead to unsafe sex.

A long-term relationship?

Overdose deaths are rare, but people can build up a tolerance to K with more needed to get the same result. Some people become dependent on it.

Using ketamine long term might cause mental health problems such as:

  • anxiety
  • depression
  • suicidal thoughts
  • memory loss.

If someone uses ketamine often they might end up with:

  • bladder problems
  • kidney or liver damage
  • stomach pains and blood in the urine.

Ketamine and the bladder

Ketamine can cause scarring and inflammation of the bladder, making the user unable to hold much urine and causing them to need to piss very often. These symptoms often lessen when ketamine use is stopped, but in some cases surgery is needed.

Some people have had to have their bladder taken out and be fitted with a bag that collects their urine.

Ketamine with other drugs


This includes ‘downers’ like alcohol, GHB/GBL, Valium and barbiturates. As K and other depressants slow the body and its functions down, the combined effect can knock the user out and/or slow their breathing and pulse to dangerous levels.

HIV drugs

Some of these, especially protease inhibitors, could theoretically raise the levels of ketamine in the body. If the user is taking protease inhibitors such as ritonavir, they should be very cautious when taking K, as they might affect ketamine metabolism in their body.


Mixing K with MDMA is not a good idea as the user can end up with dangerously high blood pressure.


Smoking cigarettes or joints when using K carries a risk of fires, as K can make people unable to move. There is also a risk of burns as K’s anaesthetic effect can stop the feeling of pain.

Useful information to know and share

  • K is usually snorted in its powder form although some people add it to drinks. However, K should never be mixed with alcohol.
  • Sometimes people smoke K mixed with cannabis in a joint, but smoking it is unpleasant and can damage the lungs.
  • If users share their injecting equipment there’s a real risk of getting or passing on infections such as HIV or hepatitis C. Injecting can also cause skin abscesses, blood poisoning, life-threatening blood clots or heart infections.
  • Someone in a K hole should be taken away from music and bright lights and reassured that it’ll be over soon and they will be OK. It can take minutes or hours to come out of a K hole, depending on how much has been taken.
  • K should be avoided by people who have fits, high blood pressure or heart or liver problems.

Next module: Speed

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