Phencyclidine (PCP) interrupts the functions of the neocortex, the section of the brain that controls the intellect and keeps instincts in check. Because the drug blocks pain receptors, violent PCP episodes may result in self-inflicted injuries.

The effects of PCP vary, but users frequently report a sense of distance and estrangement. Time and body movement are slowed down. Muscular coordination worsens and senses are dulled. Speech is blocked and incoherent.

Chronic users of PCP report persistent memory problems and speech difficulties. Some of these effects may last six (6) months to a year following prolonged daily use. Mood disorders - depression anxiety, and violent behavior - also occur. In later stages of chronic use, users often exhibit paranoid and violent behavior and experience hallucinations. Large doses may produce convulsions and coma, heart and lung failure, or ruptured blood vessels in the brain.

Lysergic acid (LSD), mescaline, and psilocybin cause delusions and hallucinations. The physical effects may include dilated pupils, elevated body temperature, increased heart rate and blood pressure, loss of appetite, sleeplessness, and tremors.

Sensations and feelings may change rapidly. It is common to have a bad psychological reaction to LSD, mescaline, and psilocybin. The user may experience panic, confusion, suspicion, anxiety, and loss of control. Delayed effects, or flashbacks, can occur even after use has ceased.

Narcotics initially produce a feeling of euphoria that often is followed by drowsiness, nausea, and vomiting. Users also may experience constricted pupils, watery eyes, and itching. An overdose may produce slow and shallow breathing, clammy skin, convulsions, coma, and possibly death.

Tolerance to narcotics develops rapidly and dependence is likely. The use of contaminated syringes may result in diseases such as AIDS, endocarditis, and hepatitis. Addiction in pregnant women can lead to premature, stillborn, or addicted infants who experience severe withdrawal symptoms.

Illegal drugs are defined in terms of their chemical formulas. To circumvent these legal restrictions, underground chemists modify the molecular structure of certain illegal drugs to produce analogs known as designer drugs. These drugs can be several hundred times stronger than the drugs they are designed to imitate.

The narcotics analogs can cause symptoms such as those seen in Parkinson's disease - uncontrollable tremors, drooling, impaired speech, paralysis, and irreversible brain damage. Analogs of amphetamines and methamphetamines cause nausea, blurred vision, chills or sweating, and faintness. Psychological effects include anxiety, depression, and paranoia. As little as one dose can cause brain damage. The analogs of phencyclidine cause illusions, hallucinations, and impaired perception.

Slang or Street Names: Ecstasy, XTC, X, Adam, Clarity, Lover's Speed

MDMA was developed and patented in the early 1900's as a chemical precursor in the synthesis of pharmaceuticals. Chemically, MDMA is similar to the stimulant amphetamine and the hallucinogen mescaline. MDMA can produce both stimulant and psychedelic effects. Thylenedioxyamphetamine (MDMA) and methylenedioxyethylamphetamine (MDMA) are drugs chemically similar to MDMA.

MDMA is taken orally, usually in a tablet or a capsule. MDMA's effects last approximately 3 to 6 hours, though confusion, depression, sleep problems, anxiety, and paranoia have been reported to occur even weeks after the drug is taken.

MDMA can produce a significant increase in heart rate and blood pressure and a sense of alertness like that associated with amphetamine use.

The stimulant effects of MDMA, which enable users to dance for extended periods, may also lead to dehydration, hypertension, and heart or kidney failure.

MDMA can be extremely dangerous in high doses. It can cause a marked increase in body temperature (malignant hypothermia) leading to the muscle breakdown and kidney and cardiovascular system failure reported in some fatal cases at raves. MDMA use may also lead to heart attack, strokes, and seizures in some users.

MDMA is neurotoxic. Chronic use of MDMA was found, first in laboratory animals and more recently in humans, to produce long-lasting, perhaps permanent, damage to the neurons that release serotonin, and consequent memory impairment.

Slang or Street Names: Grievous Bodily Harm, G, Liquid Ecstasy, Georgia Home Boy

GHB can be produced in clear liquid, white powder, tablet, and capsule forms, and it is often used in combination with alcohol, making it even more dangerous. GHB has been increasingly involved in poisonings, overdoses, date rapes and fatalities. The drug is used predominantly by adolescents and young adults, often when they attend nightclubs and raves. GHB is often manufactured in homes with recipes and ingredients found and purchased on the Internet.

GHB is usually abused either for its intoxicating/sedative/euporiant properties or for its growth hormone-releasing effects, which can build muscles.

Some individuals are synthesizing GHB in home laboratories. Ingredients in GHB, gamma-butyrolactone (GBL) and 1, 4-butanediol, can also be converted by the body into GHB. These ingredients are found in a number of dietary supplements available in health food stores and gymnasiums to induce sleep, build muscles, and enhance sexual performance.

GHB is central nervous system depressant that can relax or sedate the body. At higher doses it can slow breathing and heart rate to dangerous levels.

GHB's intoxicating effects begin 10 to 20 minutes after the drug is taken. The effects typically last up to 4 hours, depending on the dosage. At lower doses, GHB can relieve anxiety and produce relaxation; however, as the dose increases, the sedative effects may result in sleep and eventual coma or death.

Overdose of GHB can occur rather quickly and the signs are similar to those of other sedatives; drowsiness, nausea, vomiting, headache, loss of consciousness, loss of reflexes, impaired breathing and ultimately death.

GHB is cleared from the body relatively quickly, so it is sometimes difficult to detect in emergency rooms and other treatment facilities.

Slang or Street Names: Special K, K, Vitamin K, Cat Vitamin

Ketamine is an injectable anesthetic that has been approved for both human and animal use in medical settings since 1970. About 90 percent of the Ketamine legally sold today is intended for veterinary use.

Ketamine gained popularity for abuse in the 1980's when it was realized that large doses cause reactions similar to those associated with use of phencyclidine (PCP), such as dream-like states and hallucinations.

Ketamine is produced in liquid form or as a white powder that is often snorted or smoked with marijuana or tobacco products. In some cities, Ketamine is reportedly being injected intramuscularly.

At higher doses, Ketamine can cause delirium, amnesia, impaired motor function, high blood pressure, depression, and potentially fatal respiratory problems.

Low-dose intoxication from Ketamine results in impaired attention, learning ability, and memory.

Slang or Street Names: Roofies, Rophies, Roche, Forget-me Pill

Rohyphol is tasteless and odorless, and it dissolves easily in carbonated beverages. The sedative and toxic effects of Rohypnol are aggravated by concurrent use of alcohol. Even without alcohol, a dose of Rohypnol as small a 1 mg can impair a victim for eight (8) to twelve (12) hours.

Rohypnol is usually taken orally, although there are reports that it can be ground up and snorted.

The drug can cause profound "anterograde amnesia"; that is, individuals may not remember events they experienced while under the effects of the drug. This may be why one of the street names for Rohypnol is "the forget-me pill" reportedly used in sexual assaults.

Other adverse effects associated with Rohypnol include decreased blood pressure, drowsiness, visual disturbances, dizziness, confusion, gastrointestinal disturbances, and urinary retention.

Slang or Street Names: Speed, Ice, Chalk, Meth, Crystal, Crank, Fire, Glass

Methamphetamine is a toxic, addictive stimulant that effects many areas of the central nervous system. The drug is often made in clandestine laboratories from relatively inexpensive over-the-counter ingredients. It is being used by diverse groups, including young adults who attend raves, in many regions of the country.

Available in many forms, methamphetamine can be smoked, snorted, injected, or orally ingested.

Methamphetamine is a white, odorless, bitter-tasting crystalline powder that easily dissolves in beverages.

Methamphetamine is not sold in the same way as many other illicit drugs; it is typically sold through networks, not on the street.

Methamphetamine use is associated with serious health consequences, including memory loss, aggression, violence, psychotic behavior, and potential cardiac and neurological damage. Methamphetamine abusers typically display signs of agitation, excited speech, decreased appetite, and increased physical activity levels.

Methamphetamine is neurotoxic. Methamphetamine abusers may have significant reductions in dopamine transporters.

Methamphetamine use can contribute to higher rates of transmission of infectious diseases, especially hepatitis and HIV/AIDS.

Slang or Street Names: Acid, Boomers, Yellow Sunshines

LSD is a hallucinogen. It induces abnormalities in sensory perceptions. The effects of LSD are unpredictable depending on the amount taken, on the surroundings in which the drug is used, and on the users personality, mood, and expectations.

LSD is typically taken by mouth. It is sold in tablet, capsule and liquid forms as well as in pieces of blotter paper that have absorbed the drug.

Typically an LSD user feels the effects of the drug thirty (30) to ninety (90) minutes after taking it. The physical effects include dilated pupils, higher body temperature, increased heart rate and blood pressure, sweating, loss of appetite, sleeplessness, dry mouth, and tremors.

LSD users report numbness, weakness, or trembling, and nausea is common.

There are two long term disorders associated with LSD, persistent psychosis and hallucinogen persisting perception disorder (which used to be called "flashbacks").