Ketamine is classified as a schedule III drugAlso known as “Special K”, Ketamine is a prescription only Schedule III drug used to begin and maintain anesthesia during surgery. In addition to being a powerful pain reliever and sedative, The U.S. Drug Enforcement Agency includes ketamine in its list of controlled substances because of its “moderate to low potential for physiological and physical dependence”. Other Schedule III drugs include testosterone, anabolic steroids and Tylenol with codeine.

History of Ketamine

Patented in 1966 for animal and human use, it was officially approved by the U.S. FDA in 1970 for human consumption. Severely injured Vietnam soldiers received ketamine injections in the field for pain relief and anesthesia purposes. Upon returning home, Vietnam veterans who remembered how euphoric and numb ketamine made them feel probably helped popularize this drug within recreational drug user circles.

Today, the World Health Organization lists ketamine as an “essential medicine” because of its strong analgesic and anesthetic properties. According to the WHO: “ketamine…does not require reliable electricity supply, oxygen, highly trained staff or monitoring systems to administer…making ketamine critical in surgery in low- and middle-income countries and in conflict and disaster zones where such resources are often unavailable”.

Intended Use of Ketamine

Ketamine primarily acts as an antagonist for the NMDA receptor. Antagonism of this receptor results in an anesthetic and analgesic state. The patient usually becomes amnesic, hallucinogenic, and dissociative while under the effects of Ketamine. This permits the surgical procedures to be performed without the patient feeling pain or remembering the procedure. The drug works efficiently on both humans and animals, making it a preferred anesthetic for both traditional doctors and veterinarians.

Elicit Use Of Ketamine

Illicit use of ketamine is quite common, in part because the drug is much easier to obtain than other illicit drugs that produce similar effects. The main reason it is easier to obtain is because veterinarians often keep a large supply of the drug and usually have fewer safeguards than doctors or pharmacies on their medicine supply. As a result, the majority of illegal ketamine sold originally was intended for use on animals.

Another reason that it is a commonly abused drug is that it is quite easy to use. Ketamine can be injected, ingested, or snorted, all for roughly equal effect. It easily dissolves into liquid and can be easily mixed in with food. It ranks up with popular drugs like cocaine and marijuana for ease of use.

The primary benefit that addicts seeks when abusing ketamine is the hallucinatory effect which is actually considered a minor negative side effect by the medical profession. These hallucinations usually kick in within a few minutes of use and usually last for about an hour or two, depending on dosage and body weight. While experiencing these hallucinations, the user is almost always completely desensitized from the real world.

Danger of Ketamine Addiction

Ketamine is not widely considered a significant threat for addiction. Like many psychedelic drugs, it generally produces a psychological addiction, rather than a physical addiction, if it produces an addiction at all. The rare physical addiction is usually associated with a loss of appetite, nausea, and vomiting, and can easily be identified by these signs.

Ketamine’s Side Effects

The primary side effect of ketamine is an effect that is considered the primary benefit by physicians. Users of ketamine almost always enter an anesthetic state where they lose all motor functions and have no sensory connection to reality. In a controlled environment, like a surgical theater, this is not a threat. However, outside of a controlled environment, this can result in car accidents, falls, and failure to provide essential care for dependent, and social problems.

Additionally, all of the following side effects are possible with ketamine use and can be quite dangerous when medical professionals are not present to provide assistance:

  • Changes in heart rate and blood pressure
  • Rashes
  • Nausea and vomiting
  • Visual impairments, including double vision and tunnel vision
  • Respiratory difficulty
  • Anaphylaxis

Pharmacodynamics of Ketamine

Considered a dissociative anesthetic (i.e., ketamine gives users the feeling that their body is separated from their mind), ketamine molecules bind to the PCP-binding site of the NMDA receptor complex. In fact, ketamine is a derivative of phencyclidine (PCP), a 1950s pharmaceutical anesthetic later banned in the 1960s due to its unstable, hallucinogenic effects. Some opioid receptors are also implicated in promoting pharmacological symptoms of ketamine use.

In contrast to other sedating anesthetics, ketamine actually stimulates heart rate, blood pressure and other components of the cardiovascular system. When used in prescribed doses, it mildly suppresses respiration, increases release of plasma cortisol, prolactin and blood glucose and may help to reduce intraocular pressure.

Psychological & Physical Side Effects of Ketamine Abuse

When administered by professional healthcare providers, ketamine is indeed safe and useful as an anesthetic and analgesic. When taken in higher than recommended doses, ketamine will produce symptom similar to Ecstasy side effects:

  • Euphoria
  • Increased sociability
  • Dissociative sensations/living in a “different” reality
  • Depersonalization/derealization
  • Vertigo-induced nausea
  • Classic NDE visions (traveling through a tunnel, seeing dead family members, feeling beatific)
  • Auditory hallucinations

Overdosing on ketamine may cause arrhythmia, tachycardia, brachycardia, spiking blood pressure, skin rash, vomiting, double vision, severe respiratory depression and possible shock. A 2013 study investigating the long-term effects of ketamine on chronic ketamine users found that users exhibited “impaired cognitive processing speed, verbal learning and verbal fluency in addition to deficits in visual recognition memory and verbal memory”. Researchers concluded that chronic ketamine abuse caused “impairments to different areas of medial temporal and frontal functioning”.

Ketamine abuse has also been linked to serious bladder and urinary tract disorders, bladder shrinkage, incontinence and kidney damage. A review examining medical records of heavy ketamine users reported the experiences of a London urologist who had to surgically remove the damaged bladders of four out of 20 ketamine abusers. This is due to ketamine’s ability to eventually force apoptosis, or cellular death via intracellular toxin release.

Ketamine Withdrawal

While physical addiction is rare, if it should occur, ketamine has some very nasty withdrawal symptoms. In addition to enduring the above side effects at greater potency, ketamine withdrawal also commonly results in a loss of motor skills and coordination. Finally, withdrawal from ketamine is particularly difficult because a common withdrawal symptom is depression, which results in a lack of will to continue with the withdrawal process.

Since dependence and tolerance to ketamine will likely develop following extended use and abuse, ketamine addicts usually suffer addiction withdrawal symptoms including psychotic features such as false beliefs, delusions and hallucinations. Consequently, ketamine addicts should seek detoxification in a medically supervised facility, followed by addiction counseling and aftercare support.