Ketamine is a fast-acting anesthetic used in medical or veterinary surgery. If misused, it can cause harmful and long-lasting effects.

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About ketamine

Ketamine is also known as:

  • blind
  • kit kat
  • vitamin K
  • special K
  • cat tranquilizers

It is a dissociative drug, producing a sense of mind from body separation (dissociation). It works by stopping the brain from getting nerve messages about pain. It also alters how you experience sight and sound.

Ketamine is odourless and colourless. Its effects can make it difficult for you to resist sexual assault. For these reasons, ketamine is sometimes used as a date rape drug.

When health care providers use ketamine for medical purposes they inject it in a liquid form.

When sold illegally it is generally in a powder. You can take this powder:

  • smoked in a cigarette
  • sniffed up the nose (snorted)
  • mixed with a liquid and drunk
  • dissolved in a liquid and injected into a muscle or vein

Ketamine is controlled under Schedule I of the Controlled Drugs and Substances Act. Activities such as sale, possession or production of ketamine are illegal unless authorized for medical, scientific or industrial purposes.

In Canada, ketamine has legitimate uses in medicine.

Short-term effects of ketamine

Ketamine is fast acting. It affects you in minutes if taken by:

  • nose (nasally)
  • injection in a vein (intravenously)
  • injection into a muscle (intramuscularly)

Effects are much slower if you take ketamine by mouth. Ketamine use leads to short-term mental and physical effects.

Mental effects

Some of the short-term mental effects can include:

  • being unable to speak
  • a drunken, dizzy feeling
  • sleepiness, confusion and loss of coordination
  • sensations of weightlessness or inability to move
  • vivid dreams or hallucinations, which may be intense and terrifying
  • feeling like the mind is separated from the body (dissociation sometimes referred to as the "K-hole")

Physical effects

A person who uses ketamine may also experience physical symptoms, such as:

  • numbness
  • blurred vision
  • difficulty breathing
  • loss of consciousness
  • unpleasant taste in the mouth
  • increased blood pressure and heart rate, which can lead to:
    • stroke
    • accidents
    • heart attack
  • decreased response to pain, which puts the person at risk for injuries

When the effects of ketamine wear off you may feel anxious and depressed. You may also be unable to remember what happened while you were on the drug.

Ketamine can also cause nausea and vomiting. People who eat or drink before taking the drug increase their risk of choking on vomit.

Long-term effects of ketamine

With long-term use the effects of ketamine can become more severe. Common side effects for people who use ketamine regularly may include urinary and bladder problems, such as:

  • bladder inflammation
  • difficult or painful urination
  • frequent or urgent urination
  • inability to hold in urine (incontinence)

Long-term mental side effects may include:

  • flashbacks
  • impaired memory
  • decreased sociability
  • attention deficit or dysfunction

Risks related to ketamine use

If you share drug equipment such as needles and syringes you are at increased risk of infection. Contaminated equipment can spread several serious diseases, such as:

Staying at the scene of an overdose is important to help save the life of the person experiencing an overdose. The Good Samaritan Drug Overdose Act provides some legal protection for individuals who witness an overdose and call 911 or their local emergency number for help.

Using ketamine in large amounts can increase the risk of overdose. Large amounts of ketamine may depress the nervous system. This can result in effects such as:

  • coma
  • death
  • sedation
  • slowed breathing

As ketamine itself can induce overdose and is also a central nervous system depressant, co-use with other depressant drugs (including alcohol and opioids) can be dangerous. It can cause respiratory depression or stop your breathing completely. Activities that need focus and attention, like driving, also become dangerous.

Substance use disorders and withdrawal

Ketamine can be addictive. If you use it regularly your body may become tolerant of the drug's effects. This means you need to take more and more to feel the same effects.

If you stop abruptly after frequent use you can experience withdrawal syndrome. This includes symptoms such as:

  • craving
  • sweating
  • headaches

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