Source: National Institute on Drug on Drug Abuse
PCP’s forms and effects
PCP, developed in the 1950s as an intravenous surgical anesthetic, is classified as a dissociative anesthetic: Its sedative and anesthetic effects are trance-like, and patients experience a feeling of being “out of body” and detached from their environment. PCP has been used in veterinary medicine but was never approved for human use because of problems that arose during clinical studies, including delirium and extreme agitation experienced by patients emerging from anesthesia.
During the 1960s, PCP in pill form became widely abused, but the surge in illicit use receded rapidly as users became dissatisfied with the long delay between taking the drug and feeling its effects, and with the unpredictable and often violent behavior associated with its use. Powdered PCP – known as “ozone,” “rocket fuel,” “love boat,” “hog,” “embalming fluid,” or “superweed” – appeared in the 1970s. In powdered form, the drug is sprinkled on marijuana, tobacco, or parsley, then smoked, and the onset of effects is rapid. Users sometimes ingest PCP by snorting the powder or by swallowing it in tablet form. Normally a white crystalline powder, PCP is sometimes colored with water-soluble or alcohol-soluble dyes.
When snorted or smoked, PCP rapidly passes to the brain to disrupt the functioning of sites known as NMDA (N-methyl-D-aspartate) receptor complexes, which are receptors for the neurotransmitter Glutamate. Glutamate receptors play a major role in the perception of pain, in cognition – including learning and memory – and in emotion. In the brain, PCP also alters the actions of dopamine, a neurotransmitter responsible for the euphoria and “rush” associated with many abused drugs.
At low PCP doses (5 mg or less), physical effects include shallow, rapid breathing, increased blood pressure and heart rate, and elevated temperature. Doses of 10 mg or more cause dangerous changes in blood pressure, heart rate, and respiration, often accompanied by nausea, blurred vision, dizziness, and decreased awareness of pain. Muscle contractions may cause uncoordinated movements and bizarre postures. When severe, the muscle contractions can result in bone fracture or in kidney damage or failure as a consequence of muscle cells breaking down. Very high doses of PCP can cause convulsions, coma, hyperthermia, and death.
PCP’s effects are unpredictable. Typically, they are felt within minutes of ingestion and last for several hours. Some users report feeling the drug’s effects for days. One drug-taking episode may produce feelings of detachment from reality, including distortions of space, time, and body image; another may produce hallucinations, panic, and fear. Some users report feelings of invulnerability and exaggerated strength. PCP users may become severely disoriented, violent, or suicidal.
Repeated use of PCP can result in addiction, and recent research suggests that repeated or prolonged use of PCP can cause withdrawal syndrome when drug use is stopped. Symptoms such as memory loss and depression may persist for as long as a year after a chronic user stops taking PCP.
Nature and effects of Ketamine
Ketamine (“K,” “Special K,” “cat Valium”) is a dissociative anesthetic developed in 1963 to replace PCP and currently used in human anesthesia and veterinary medicine. Much of the Ketamine sold on the street has been diverted from veterinarians’ offices. Although it is manufactured as an injectable liquid, in illicit use Ketamine is generally evaporated to form a powder that is snorted or compressed into pills.
Ketamine’s chemical structure and mechanism of action are similar to those of PCP, and its effects are similar, but Ketamine is much less potent than PCP with effects of much shorter duration. Users report sensations ranging from a pleasant feeling of floating to being separated from their bodies. Some Ketamine experiences involve a terrifying feeling of almost complete sensory detachment that is likened to a near-death experience. These experiences, similar to a “bad trip” on LSD, are called the “K-hole.”
Ketamine is odorless and tasteless, so it can be added to beverages without being detected, and it induces amnesia. Because of these properties, the drug is sometimes given to unsuspecting victims and used in the commission of sexual assaults referred to as “drug rape.”
Nature and effects of Dextromethorphan
Dextromethorphan (sometimes called “DXM” or “robo”) is a cough-suppressing ingredient in a variety of over-the-counter cold and cough medications. Like PCP and Ketamine, Dextromethorphan acts as an NMDA receptor antagonist. The most common source of abused Dextromethorphan is “extra-strength” cough syrup, which typically contains 3 milligrams of the drug per milliliter of syrup. At the doses recommended for treating coughs (1/6 to 1/3 ounce of medication, containing 15 mg to 30 mg Dextromethorphan), the drug is safe and effective. At much higher doses (4 or more ounces), Dextromethorphan produces dissociative effects similar to those of PCP and Ketamine.
The effects vary with dose, and Dextromethorphan users describe a set of distinct dose-dependent “plateaus” ranging from a mild stimulant effect with distorted visual perceptions at low (approximately 2-ounce) doses to a sense of complete dissociation from one’s body at doses of 10 ounces or more. The effects typically last for 6 hours. Over-the-counter medications that contain Dextromethorphan often contain antihistamine and decongestant ingredients as well, and high doses of these mixtures can seriously increase risks of Dextromethorphan abuse.
