Phencyclidine (PCP)

Phencyclidine (PCP, sernylan, sernyl) is a crystalline substance soluble in water, methanol, ethanol and methylene chloride. The base of phencyclidine, on the contrary, is almost insoluble in water, but easily soluble in methanol, toluene, and methyl acetate.

The illegal sale of PCR comes in the form of tablets or capsules for oral administration or powder for inhalation through the mouth or nose. Liquid forms for intravenous injections are less common. They are sold packaged in small vials or glass bottles of small volumes. The slang name among drug addicts is angel dust.

History:
Phencyclidine was first synthesized by Parke in 1956.

In 1963, it was patented as a means for anesthesia under the trademark sernyl. Unlike opiates, it does not inhibit cardiovascular activity or respiration. However, in the course of clinical use, toxic side effects were identified, including postoperative hallucinations, arousal, mental disorders and depressive states, and, despite the good therapeutic properties, the drug was supplanted by ketamine. It became commercially available for use as a veterinary anesthetic in the 1960s under the brand name sernylan. In 1978-79, due to the significant use of PCP, commercial production of Sernilane was completed, it was withdrawn from circulation and banned for use.

The interest of the US military in phencyclidine did not weaken for 15 years, from 1958 to 1972. During this time, 1,500 volunteers experienced its effects. In the USA, tests have traditionally been conducted in the laboratories of the Edgewood Arsenal. Under the code name product P was in service with the South African Army. Simple and cheap synthesis, experimental data accumulated over many years and relatively low toxicity – these properties of PCP can still return it to the battlefields of future battles.

The first cases of PCP abuse were reported in San Francisco in 1967. Due to its cheapness, PCP began to spread rapidly as a street drug, first in the United States, and then in Western Europe. PCP was often sold to unsuspecting drug addicts under the guise of LSD, mescaline or added to marijuana.

In 1984, phencyclidine appeared on the black markets of Moscow and St. Petersburg. Phencyclidine is illegally sold under a number of other names, including such as angel dust, supertrava, killer weed. In its pure form, it is a white transparent powder that immediately dissolves in water. However, most PCP on the illegal market contains a certain amount of pollutants due to improvised production, which changes color from yellowish-brown to brown and a consistency that ranges from powder to adhesive mass. It is sold not only in tablets and capsules, but also in powder or liquid form, then added to leaf material such as parsley, mint, oregano or marijuana, or smoked.

Application and action:
The effects of drugs are as diverse as their appearance. A small amount of PCP often makes consumers feel isolated, restrained and distant from their environment. Numbness, slurred speech and loss of coordination can be accompanied by a sense of strength and invulnerability. Meaningless gaze, rapid and involuntary eye movements, as well as a quick gait are the most pronounced symptoms.

Auditory hallucinations, image distortion, serious mood disorders and amnesia may also be observed. In some addicts, PCP can cause severe anxiety and a sense of imminent death; in others, paranoia and fierce hostility; in others, it can cause psychoses indistinguishable from schizophrenia. Many believe that PCP is one of the most dangerous drugs used.

A change in the production process can lead to the appearance of chemically similar analogues capable of producing a mental effect similar to PCP.

With intravenous administration of 0.1 mg / kg, psychoactive properties are already manifested. The action develops in 2 minutes. After intravenous administration of 0.5 mg / kg of PCR, the maximum plasma content of 1 mcg / ml is 1.5 hours, then the concentration of PCR decreases: after 12 hours to 10 ng / ml, after 15 hours to 5 ng / ml, after 24 hours to 1 ng / ml. The area of toxic concentrations in plasma is defined as 7-240 ng/ml, the area of lethal concentrations 1-5 mcg/ml.

The onset of action with oral or intranasal administration (nasal retraction) occurs after 30-45 minutes. The maximum plasma concentration is set after 2 hours. For oral administration or inhalation, mixtures of PCR with other narcotic drugs are also often used: cocaine, opiates, amphetamine, LSD. More than 30 mixtures in illegal circulation containing PCR have been registered.

The effective concentration of phencyclidine during inhalation exposure in combat conditions is in the range of 250 – 3000 mg · min / m3. The appearance of the first symptoms of poisoning from 15 seconds to 2.5 minutes. Toxicity to animals (inhalation of aerosol): mice – 22,000 mg·min/m3; Rats, guinea pigs – 115,000 mg·min/m3.

The drug is also smoked in a tube or in the form of cigarettes. Due to the very high temperature and irritating effect of PCR smoke on the mucous membranes of the mouth and throat, many users of this drug use mint leaves or substances with a similar “cooling” effect while smoking. When smoking, due to pyrolytic cleavage to 1-phenyl-cyclohexene, acetylpiperidine and piperidine, only about 30% of the initial dose of PCR is injected into the body. The action develops in 2 minutes. The maximum plasma concentration is set after 10 minutes.

According to the mechanism of action, PCP refers to dissociative anesthetics, blockers of N-methyl-D-aspartate (NMDA) neuroreceptors.

PCR is easily absorbed and distributed to peripheral organs (mainly in liver and brain tissues), remaining only in very small amounts in the circulatory system, which is reflected in the large volume of distribution, which is 6.2 l/kg. The time of T(1/2) half-life in plasma is 7 hours. The duration of the effects is 4-6 hours, regardless of the method of administration. If you take too high doses, symptoms can last up to 48 hours.

The bioavailability of PCR is 50-90%. Biological fluids and tissues of newborns whose mothers used phencyclidine during gestation and feeding may contain the drug in significant quantities. There was a case when the content of PCR in the urine and meconium (primordial feces) of a newborn was 150 ng/ml and 938 ng/g, respectively, while the concentration of PCR in the mother’s urine was 287 ng/ml.

Effects of PCR:

External manifestations:
Absent (meaningless) gaze; muscle rigidity (tension); mimic grimaces, erratic movements or, conversely, numbness, nystagmus (involuntary rapid movements of the eyeballs); slow and blurred speech sometimes – speech excitement; ataxia (impaired coordination of movements); increased pain threshold (decreased susceptibility to pain); severe a feeling of heat, severe sweating – an increase in body temperature; passivity or lethargy, which can suddenly be replaced by motor excitement; nausea, vomiting, salivation.

Mental manifestations:
Small doses cause a state resembling alcoholic intoxication, large doses cause disorientation, loss of orientation in time and space; experiences can vary from a state of ecstatic pleasure to an attack of real paranoia; memory impairment; hallucinations: visual, auditory and tactile, and often the content of hallucinations can be controlled; loss of a sense of identity.

PCR is characterized by tolerance, which can reduce the severity of the effects of its reception.

Withdrawal time (detection) PCP and metabolites:
The main amount of the administered dose of PCR is excreted in the urine in the form of conjugated metabolites: 30-50% of the dose (1 mg of PCR intravenously) is excreted in 7 hours and 77% of the dose in 10 days, while 73% in the form of conjugates of hydroxylated metabolites and only 10% (according to other data up to 30%) in the form of the starting compound.

In the majority (approximately 85%) of cases associated with the consumption of PCR, its concentration in biofluids is very small – below 30 ng/ml, especially 2-4 days after consumption. The excretion of PCR increases with metabolic acidification of urine, but it does not affect the excretion of metabolites. The values of the half-life of PCR, given in various sources, vary in a wide range from 8 to 55 hours, averaging 18 hours. The detection interval of PCR in the urine after taking a single dose can reach up to 7 days, with chronic use up to 20 days.

Danger:
There are cases when, under the influence of high doses of PCP, people tried to stop the train, jumped off rocks and threw themselves out of windows, climbed into a cave to a polar bear to take photos. Treatment of poisoning: Aminazine (100 mg 4 times a day) or haloperidol is used to relieve arousal.

With chronic use, tolerance and addiction develop rapidly. Withdrawal syndrome lasts for several days, accompanied by severe depression and disorientation.

The consequences of long-term abuse of PCP: from depression, memory impairment and difficulties in conversation to severe mental disorders and profound personality changes. Causes exacerbation of existing mental illnesses, especially schizophrenia. Dissociative anesthetics (PCP, ketamine, dextromethorphan, MK-801) cause neurotoxic brain damage in humans, known as Olney’s Lesions, or Olney’s lesion. More often, the lesion develops in drug addicts who have been taking large doses of dissociatives for a long time.