Mixing PCP with other drugs is very high-risk behavior. Due to the unpredictable nature of PCP side effects
, many risks that do not exist with other drugs of abuse become more prevalent with PCP.
Alcohol – Sedative narcotics such as PCP raise the risk of overdose in combination with use of other sedative medications, including alcohol. Because the risk for hallucinations and delusional thinking and behavior is so high with PCP use, alcohol can increase the likelihood of reduced inhibitory markers, allowing the user to increase risky behaviors and suicidal ideation.
Antidepressants – The effects on the brain of both PCP and antidepressant medications are very similar. While this is an established effect with use of antidepressants for prescribed users, introduction of PCP along with these medications is likely to increase the effects in dangerous ways. The mechanisms of operation for both types of medication have been recognized to be effective in creating a distancing, detached state that may become seriously implicated for suicidal ideation and attempts, especially in the under 18 year old brain.
Antipsychotics – When combined with antipsychotics, PCP symptoms may be reduced. This is good information for those who seek to treat the long-term or permanent damage done by PCP usage. However, there are only a few of these drugs that effectively offset the chemical reaction of PCP in the brain. The research is ongoing to discover the inhibitory aspects of anti-psychotic medications on the receptor sites damaged through PCP use.
There is little or no evidence that use of PCP by those who are taking anti-psychotic medications would be more or less likely to experience psychotic responses to the use of PCP. Because of the nature of the mental illness being treated by anti-psychotic medication, PCP may increase the risk of psychotic experiences for this population. The confounding factor of hallucinations and/or delusions is hard to determine causally.
Other risks with sedative mixers and PCP is that of the depressed state of the central nervous system, which is not incrementally affected by use of these two in combination, but synergistically affected, creating a much higher risk than that of just each component. The effects are dangerously multiplied with this combination, which also includes risk of overdose and cessation of breathing functions, heart stoppage and death.
Benzodiazepines – Users combining PCP with benzodiazepine medications are running the same risks as that of drinking alcohol with PCP use. The increased risk of overdose is higher than with other combinations of drugs.
Most often, death from PCP use is caused by suicide, rather than overdose. This risk is increased by use of PCP with benzodiazepines.
Heroin – The dangers of using PCP with heroin and other Central Nervous System depressants, such as alcohol, benzodiazepines, and even marijuana are similar. All side effects are increased, and cessation of breath and heart function are intensified tremendously with use of these combined medications.
Marijuana – Use of marijuana while on PCP is frequent, because many users put liquid PCP on pot and smoke it. Again, the risk is that of the depressed state of the central nervous system. Due to the hallucinogenic and delusions created with PCP use, risk with marijuana is that of increased occurrence of paranoia and psychosis that may become permanent.
The dangers of antidepressants on this population are well-known and documented. Increased risks are likely to be present with the addition of PCP to the mix. Detachment of both behaviors and emotional responses seen with PCP would most often be seen as loss of control of rational thinking and delusions that would lead to high-risk behaviors and lack of understanding of consequences/outcomes of such behavior. Also irrational and psychotic behaviors may be more pronounced with this combination of drugs.