A phencyclidine (PCP) screen is a test that detects the presence of PCP in urine. PCP is a hallucinogenic dissociative drug that is used as a veterinary anesthetic and was first developed as an anesthetic for humans in the 1950s. However, it was taken off the market for human use because it sometimes caused hallucinations. PCP is illegal, but it is easily manufactured and available in a number of forms, including a pure white crystal-like powder, a tablet or capsule, and it can be swallowed, smoked (alone or with marijuana), sniffed, or injected. False positive results on PCP urine drug testing can occur due to the use of certain medications. The effects of PCP are very much dose-related, and small amounts of PCP can produce alertness, wakefulness, increased energy, increased heart rate, and decreased sense of pain and touch, and an overall feeling of well-being. Large doses of PCP can result in death due to convulsions, heart and lung failure, and coma.