PCP (Phencyclidine): short-term and long-term health effects

Phencyclidine (PCP) is a Schedule II substance with hallucinogenic effects and the potential for abuse and addiction. PCP is more commonly known as angel dust, among other names. People use it as a club drug to become more euphoric or excited. However, PCP induces hallucinogenic effects that lead to detachment from reality. 

The drug can cause numerous short- and long-term health effects. The most common short-term effects include euphoria, distortion of sounds and images, depersonalization, loss of balance and coordination, acute anxiety, fear of impending doom, numbness in arms and legs, and many others.

Long-term phencyclidine effects range from speech difficulties and memory problems to anxiety and depression, social withdrawal, suicidal thoughts, and flashbacks.

The drug may put a person in danger and increase the risk of injuries and accidents.

What is Phencyclidine (PCP)?

Phencyclidine (PCP) is a dissociative hallucinogenic drug that was initially developed as a general anesthetic. The drug was first synthesized by Victor Maddox, a chemist from Michigan. Parke, Davis, and Company (now a subsidiary of Pfizer) marketed PCP as an anesthetic in 1956. At the time, PCP was known as Sernyl.

What is PCP made of? This synthetic drug is made from a combination of compounds and chemicals such as potassium cyanide, hydrochloric acid, ether, and bromobenzene. 

In a nutshell, Phencyclidine (PCP) is a bitter-tasting, white crystalline powder that easily dissolves in alcohol or water. 

The United States Drug Enforcement Administration classifies PCP as a Schedule II drug. Schedule II indicates a substance has a high potential for abuse, with use leading to potentially severe physical and psychological dependence. That is why the use of PCP is illegal, which applies to other substances from the PCP drug class too.

The use of PCP as an anesthetic has been discontinued, but it has become a popular club drug. People use PCP to achieve euphoria and for its hallucinogenic effects.

In most cases, PCP is sold in its original form, and it can be ingested orally, smoked, snorted, and injected. It comes in the form of tablets and capsules, but it’s also possible to get it in powder or liquid forms. People tend to smoke PCP drugs together with marijuana, tobacco, and other plant leaves. They also dissolve PCP in a liquid where they dip joints or cigarettes.

When PCP is smoked, injected, or snorted, a person typically feels the effects within two to five minutes. Oral ingestion of PCP has a longer onset of action; it may take 30 to 60 minutes for the drug to kick in. 

The effects of PCP usually last six to 24 hours, but sometimes their duration is up to 48 hours. Although some people consider PCP a harmless party drug, repeated use can lead to tolerance, dependence, and addiction. 

The first reports of PCP abuse were recorded in the 1960s in Haight Ashbury, San Francisco. This district was known as one of the most popular spots among followers of the hippie movement. 

1. Euphoria

Euphoria is a state of intense happiness and excitement. At lower doses, PCP makes a person euphoric. Even though this subject requires further research, euphoria after PCP use could result from changes in brain chemicals. Dopamine is the main chemical in the brain that is responsible for euphoria. Phencyclidine can act on dopamine and create a “fertile ground” for a short-term wave of euphoria. In fact, people choose PCP to experience this intense excitement and happiness. 

While PCP can cause euphoria, it’s important to keep in mind this effect is short-term. Chronic use of PCP has the opposite effect and may lead to depression in the long run. In other words, using PCP to lift mood and make feel happy is not recommended. 

Euphoria, caused by PCP, could also lead to engaging in risky behaviors and reckless decisions.

2. Distortion of sound, image, and body

Distortion of sound, image, and body refers to the impaired perception of sight, sound, and reality. As a hallucinogen, PCP affects the way people perceive what they hear or see. For that reason, they may struggle with distorted images, sizes, and sounds. As a result, a person may feel as if they’re hearing colors or seeing sounds. This happens due to alteration of functional connectivity in the brain due to PCP use.

Imbalances of neurotransmitters such as acetylcholine could be behind this effect of PCP. Although this health effect is short-term, it can have a major impact on a person’s mental health. Distorted sounds and images can further contribute to hallucinations, psychosis, and panic attacks, all of which put a PCP user in danger.

3. Depersonalization and detached feelings

Depersonalization is the feeling of being disconnected or detached from oneself and their surroundings. Hallucinogens such as PCP can cause depersonalization and detached feelings among users.

The exact cause of depersonalization disorder among PCP users, and people who use other substances, is unknown. Symptoms of depersonalization could be linked to disconnection of a cortico-limbic brain system which involves prefrontal structures, amygdala, and anterior cingulate cortex (ACC), a paper from the Current Psychiatry Reports explained. 

Disruption of social behavior in PCP users involves dysfunction of the amygdala. At the same time, PCP affects the prefrontal cortex and ACC, which are involved in processing behavior and emotion. 

By affecting these important parts of the brain, PCP could cause extreme effects such as one’s detachment from reality, emotions, and surroundings.

4. Loss of balance and coordination

Loss of balance and coordination is known as ataxia. One of the most pronounced short-term PCP symptoms is impaired muscle coordination and balance. Ataxia usually happens due to damage to the cerebellum and its connections. The cerebellum is part of the brain that controls muscle coordination. 

While PCP is usually explored for its impact on the hippocampus, evidence also shows it affects the cerebellum. That means that by acting on this specific part of the brain, PCP can lead to impaired coordination and balance. This puts a PCP user at a higher risk of falls, injuries, and other accidents. 

Studies show that decreased glutamate concentration can also contribute to ataxia. Phencyclidine acts as a glutamate antagonist. This could also explain problems maintaining balance or staying coordinated among PCP users.

5. Loss of sensation and inability to feel pain

The loss of sensation and inability to feel pain (analgesia) can be partial or total. The use of PCP can lead to the inability to feel pain for a while. This happens because PCP acts on NMDA and other receptors that are involved in pain sensation. Also, PCP affects opioid receptors, which participate in regulating pain and other functions such as reward and addictive behaviors.

Impaired functioning of receptors that receive signals and help control pain can lead to a lack of pain sensation among people who use PCP. For example, these receptors can become too weak to receive and process pain signals. 

Lack of pain sensation may seem like a good thing, but it can be dangerous. This puts a PCP user at a higher risk of accumulating wounds, bruises, and other health issues that go undetected. 

6. Acute anxiety, agitation, and mood swings

Acute anxiety is severe anxiety and panic that can be so powerful they make a person feel like they have a heart attack. Agitation is an unpleasant condition of extreme arousal and restlessness. Mood swings are sudden or intense changes in emotional states. The use of PCP can cause acute anxiety or make a person agitated, easily irritated, frustrated, or moody. 

Acute anxiety and other problems occur due to a sudden change in neurotransmitters with PCP use. In some people, the effects of PCP can be so unpredictable and cause erratic behavior and panic attacks. Acute anxiety can manifest itself through panic attacks in addition to other symptoms such as heart palpitations (pounding heart) and chest pain.

The neurotransmitter that plays a major role in acute anxiety symptoms, including acute anxiety and panic attacks, is norepinephrine. Serotonin also plays a role. Since they regulate some functions and emotions that affect the onset of anxiety, changes in these neurotransmitters are underlying causes of panic attacks and other symptoms. As seen further in this post, PCP acts on these neurotransmitters and affects their functioning.

7. Fear of impending disaster

Fear of impending disaster (or doom) is an impression or sensation that something horrible or tragic is about to happen. Phencyclidine users may experience undesirable feelings such as fear of impending doom due to the physical and psychological effects of the drug. 

Taking PCP can increase body temperature and blood pressure and increase heart rate. At the same time, PCP can trigger anxiety and its symptoms, including shortness of breath. When these symptoms are combined with dissociative effects and hallucinations, PCP users may feel like they’re facing inevitable danger. 

8. Numbness in the arms and legs

Numbness is the loss of sensation in a specific part of the body, in this case, the extremities. Even low to moderate doses of PCP can cause numbness throughout the body and loss of coordination. In most cases, PCP makes a person’s arms and legs feel numb.

Drug-induced paresthesia (numbness) usually occurs in the form of tingling or numbness, burning sensation, pins and needles, and even itching. This effect is usually spontaneous, but sometimes external stimuli can trigger it.

It’s not clear why PCP causes numbness in the arms and legs, but it’s likely due to its influence on neurotransmitters and various receptors in the brain. This drug can cause “confusion” among receptors and chemical messengers that convert to physical effects such as numbness in extremities. At this point, evidence on this subject is scarce. However, studies show serotonin reuptake inhibitors can cause numbness, even during withdrawal, during which serotonin receptors are hypersensitive, and it could cause tingling in arms and legs. That’s important because PCP can also inhibit the reuptake of serotonin (learn more about it below).

1. Stuttering and speech difficulties

Stuttering is characterized by the repetition of syllables or words, their prolongation, and interruptions in speech. With long-term use of PCP, people develop major speech difficulties that include trouble articulating, inability to speak, and stuttering. People with speech difficulties tend to isolate themselves from their family and friends.

Evidence confirms that PCP-related problems often manifest themselves in the form of speech difficulties, but the underlying mechanisms behind this effect are unclear. The World Journal of Psychiatry published an interesting review that explored drug-induced stuttering. The review showed that impaired neurotransmission of dopamine could contribute to this speech difficulty. Drugs or substances that impair glutamate neurotransmission can also contribute to stuttering. This is important because PCP affects neurotransmission and balance of both dopamine and glutamate.

Speech difficulties make it difficult for a person to express themselves, which deepens their depression. People who abuse PCP often have reasoning problems (see below), which affect their thinking. Combining these two health effects makes PCP even more dangerous than people believe.

Stuttering is characterized by the repetition of syllables or words, their prolongation, and interruptions in speech. With long-term use of PCP, people develop major speech difficulties that include trouble articulating, inability to speak, and stuttering. People with speech difficulties tend to isolate themselves from their family and friends.

Evidence confirms that PCP-related problems often manifest themselves in the form of speech difficulties, but the underlying mechanisms behind this effect are unclear. The World Journal of Psychiatry published an interesting review that explored drug-induced stuttering. The review showed that impaired neurotransmission of dopamine could contribute to this speech difficulty. Drugs or substances that impair glutamate neurotransmission can also contribute to stuttering. This is important because PCP affects neurotransmission and balance of both dopamine and glutamate.

Speech difficulties make it difficult for a person to express themselves, which deepens their depression. People who abuse PCP often have reasoning problems (see below), which affect their thinking. Combining these two health effects makes PCP even more dangerous than people believe.

2. Reasoning and memory problems

Reasoning and memory problems refer to experiencing difficulties with logical or sensible thinking and forming memories or remembering information. Taking PCP can take its toll on your cognitive abilities, such as reasoning and memory. With long-term use of this drug, people can experience learning and memory deficiencies that impair their daily functioning.

A study from the Journal of Molecular Neuroscience found that PCP use exhibits down-regulatory effects on BDNF mRNA levels in the brain. Here, BDNF stands for brain-derived neurotrophic factor, a key molecule responsible for plastic changes associated with memory and learning. The drug acts on the prefrontal cortex and hippocampus, which could lead to problems with cognitive functioning. This explains why people who use PCP tend to experience reasoning and memory problems.

After all, an impaired level of BDNF can disrupt the balance between excitatory and inhibitory neurotransmission in the brain. As a result, the brain loses synaptic refinement, which leads to impaired long-term potentiation, learning, and memory.

Plus, PCP acts on NMDA and acetylcholine neurotransmitters in the hippocampus. When that happens, the brain loses the ability to encode information, which is necessary for transferring this info to long-term memories. Long-term use of PCP can damage neurons that perform these roles. That’s why people experience memory issues long after they stop taking PCP. 

Experiencing memory and reasoning problems has a major impact on a person’s quality of life and may further contribute to emotional struggles. That happens because failing to remember and store information can be quite stressful for a person. 

3. Anxiety and depression

Anxiety is an intense, excessive, or persistent feeling of unease, fear, and worry. Depression is a mood disorder indicated by a persistent feeling of sadness, helplessness, and loss of interest. One of the most pronounced long-term health effects of PCP use is the development or worsening of depression and anxiety. Even low doses of PCP can cause these mental health problems.

Pharmacology Biochemistry and Behavior published a study that showed that withdrawal from a single dose of PCP could alter behavior and affect anxiety. The same study revealed effects of PCP on anxiety depend on age and gender. For instance, PCP is anxiogenic (causes anxiety) in males and anxiolytic (reduces anxiety) in females. 

However, with repeated use, PCP can either contribute to the development of anxiety or worsen symptoms in people who already have it. Although more research is necessary to determine why anxiety is one of the long-term effects of PCP, it could be due to the drug’s impact on neurotransmitters such as serotonin, dopamine, and norepinephrine.

A paper from the Forensic Science Review reported that PCP exhibits stimulant, analgesic, hallucinogenic, and depressant effects. It’s unpredictable which of these effects a person will experience. It depends on their personality, environment of use, and psychological state. 

In order to understand why PCP causes depression, it’s important to bear in mind the abovementioned neurotransmitters are implicated in this mood disorder too. Abuse of PCP can create a chemical imbalance that triggers depression. At the same time, depression can contribute to worsening other long-term effects of PCP, including suicidal thoughts, social withdrawal, and others.

4. Suicidal thoughts

Suicidal thoughts or ideation are a serious problem wherein a person actively thinks about taking their own life. Long-term use of PCP can lead to suicidal thoughts primarily due to the severe depression that people experience. At the same time, chronic PCP use triggers the feeling of detachment that could also contribute to suicidal ideation. 

A paper from the International Journal of Molecular Sciences explains that impaired regulation of glutamate neurotransmission and NMDA receptors play a role in suicide. That happens because they lead to impulsivity and cognitive dysregulation. This finding is important because PCP acts on glutamate and NMDA. The long-term use of the drug can intensify the effects of PCP on the nervous system and further contribute to this damage, thus contributing to suicidal thoughts.

5. Isolation and retreat from society

Isolation or retreat from society is avoidance of interacting with other people or bringing communication with others to a minimum. Long-term use of PCP leads to social withdrawal, but the underlying mechanisms are unclear. It was theorized social withdrawal was due to anxiety among PCP users. However, a study from Behavioral Pharmacology found that anxiety scores were unchanged in PCP-treated animals, thus suggesting their social withdrawal doesn’t result from this factor.

However, PCP is known for its potential to induce psychosis symptoms, and social withdrawal is one of them. For that reason, phencyclidine’s role in encouraging psychosis could be behind a person’s tendency to spend more time alone and isolate oneself from friends and family. Hallucinations also contribute to this behavior.

6. Flashbacks

A flashback is a vivid experience wherein a person relives some aspects of traumatic events and other situations as if they are happening at the moment. Long-term use of PCP can lead to a condition called hallucinogen persisting perception disorder (HPPD). Basically, HPPD is a non-psychotic disorder that involves persistent or lasting visual hallucinations or perpetual distortions.

A person can experience flashbacks even if they haven’t used PCP lately. That happens because PCP can cause flashbacks days, weeks, or months after the last use. According to a paper from Frontiers in Psychiatry, HPPD is a potentially permanent syndrome. It’s not entirely clear how PCP causes flashbacks, but it could be down to impaired serotonin neurotransmission. Users of PCP tend to be vulnerable, or predisposed, to continue centrally processing visual imagery after the visualization has been eradicated from their visual fields. In other words, some people are prone to experiencing flashbacks caused by PCP and other psychedelics. 

Flashbacks can have physical and psychological, or emotional symptoms. For example, a person with HPPD may notice intensified colors or flashes of color and color confusion, experience size confusion, see halos around objects, and see geometric patterns. Difficulty reading and feeling uneasy are also symptoms of HPPD. Additionally, HPPD can also cause anxiety and panic, suicidal thoughts, and depersonalization or derealization.

How does PCP impact the nervous system?

PCP impacts the nervous system by acting on several neurotransmitters. Mainly, PCP inhibits the reuptake of norepinephrine, dopamine, and serotonin. Inhibiting the reuptake of neurotransmitters refers to increasing their concentrations. This is achieved by preventing neurons from reabsorbing (reuptake) them. 

Reuptake is a normal function. Inhibiting this activity leads to excessive levels of their neurotransmitters and consequences such as increased wakefulness and energy. Insomnia, agitation, and decreased appetite can also happen as a result.

Additionally, PCP also blocks NDMA receptors to interrupt the activity of glutamate. These particular receptors are responsible for emotions, pain sensation, memory, and learning. By impairing these receptors, PCP enables the brain to disconnect from reality or normal sensory experiences. That said, higher PCP doses can exhibit excitatory effects on NDMA receptors.

Studies also show PCP interacts with mu opioid, sigma, nicotinic, and muscarinic receptors. These receptors are implicated in various conditions, including addiction, pain, and depression. 

Since PCP acts mainly on neurotransmitters, it impairs delicate balance in the brain, and the “messages” get mixed up. This could lead to PCP psychosis and other effects, but further research is necessary to elucidate the exact mechanism of action through which PCP works or acts on the brain. 

What are the slang terms for PCP?

Slang terms for PCP drugs include angel dust, kools, hog, lethal weapon, rocket fuel, jet fuel, happy sticks, peace pill, DOA, trank, killer weed, ozone, wack, supergrass, Bella donna, and cliffhanger. 

Other PCP street names include angel mist, angel hair, gorilla tab, gorilla biscuits, green leaves, horse tracks, horse tranquilizers, juice, Kaps, k-blast, leaky leak, love boat, mad dog, mad man, magic dust, and mean green.

People may also use other names to refer to PCP. These include mist, monkey dust, new acid, new magic, orange crystal, Paz, peep, peace pill, Peter Pan, pig killer, purple rain, puffy, red devil, rupture, stardust, spores, sherms, surfer, tic tac, taking a cruise, zombie, yellow fever, wobble weed, wolf, wet, worm, white horizon, tish, and venom.

The terms wet and zoom refer to combining PCP with marijuana. Names for a combination of PCP and cocaine include whack and space. Alien sex friend is a combination of PCP and heroin, whereas black acid is a slang term for mixing PCP with LSD. Domex is a slang term for mixing PCP with MDMA, Clinical Pain Advisor reports.

How to withdraw from PCP?

Tips on how to withdraw from PCP are listed below.

• Adhere to the PCP addiction treatment religiously 
• Attend all therapy sessions regularly
• Find new interests and activities to replace PCP abuse
• Identify triggers that increase PCP use and avoid or reduce exposure to them
• Exercise regularly and eat a well-balanced diet
• Address the underlying problem such as depression, anxiety, or other issues that contribute to PCP abuse
• Relearn how to live without drugs by saying no or avoiding people who use PCP

The PCP withdrawal can be long-lasting and uncomfortable because the drug binds to the brain and fat tissue in the body. As a result, it takes several days for PCP to clear from the body. Withdrawal symptoms can be physical and psychological. 

For that reason, medical supervision is the best option. These symptoms usually occur during detox, i.e., the first stage of addiction treatment. During this time, patients learn to identify triggers, which can be people, things, or situations that make them want to use PCP. Doing so is important for withdrawal from PCP and more successful treatment.

The duration of withdrawal is different for each patient because several factors play a role. These factors include the length of PCP addiction, dosages taken, overall physical and mental health, and whether a person is using other substances too. For that reason, one shouldn’t compare their withdrawal efforts and progress to someone else’s.

Is PCP the cause of schizophrenia?

PCP is not the cause of schizophrenia, but it can worsen this (or other) mental health condition in people who have it and mimic the symptoms in individuals with no prior psychiatric illness. 

A review from the Journal of Psychology reported that PCP could induce symptoms of schizophrenia in healthy people. These symptoms last anywhere from a few days to more than a week. 

According to a paper from the California Journal of Emergency Medicine, one of the most unusual features of PCP is that it induces psychosis or syndrome that mimics schizophrenia at doses of 5mg to 10mg orally. Doses higher than 10mg lead to coma.

It’s not clear why that happens, but neurotransmitter glutamate and N-methyl-D-aspartate (NMDA) could play a role. Glutamate is the most abundant excitatory neurotransmitter. On the other hand, NMDA participates in learning and memory, especially spatial memory. 

The PCP acts as an antagonist of both glutamate and NMDA, i.e., it inhibits their activity. Glutamate abnormalities are present in people with schizophrenia. Since PCP inhibits NMDA, exposing the developing brain to this drug could cause neurobehavioral deficits. 

For example, one study found that perinatal exposure to PCP can impair neuronal development and induce long-lasting behaviors similar to schizophrenia in adulthood.

The potential of PCP to induce psychosis or mimic schizophrenia symptoms could serve a good purpose because scientists can use it in studies to develop medications and better treatments for this mental health condition.