Symptoms of use:

• needle marks on the skin in some cases (called "tracks")
• scars from skin abscesses
• rapid heart rate
• constricted pupils (pinpoint)
• relaxed and/or euphoric state ("nodding")
• coma, respiratory depression leading to coma and death in high doses

Symptoms of withdrawal:

• anxiety and difficulty sleeping
• sweating
• goose bumps (piloerection)
• runny nose (rhinorrhea)
• stomach cramps or diarrhea
• dilated pupils
• nausea and vomiting
• excessive sweating
• increase in blood pressure, pulse, and temperature

CENTRAL NERVOUS SYSTEMSTIMULANTS

Symptoms of cocaine use:

• euphoria (exaggerated feeling of well-being)
• dilated pupils
• rapid heart rate
• restlessness and hyperactivity

Symptoms of cocaine withdrawal:

• fatigue and malaise
• depression
• vivid and unpleasant dreams

CENTRAL NERVOUS SYSTEM DEPRESSANTS

Symptoms of alcohol use:

• slurred speech
• lack of coordination
• decreased attention span
• impaired judgment

Symptoms of alcohol withdrawal:

• anxiety
• tremors
• seizures
• increase in blood pressure, pulse, and temperature
• delirium

HALLUCINOGENS

Symptoms of LSD use:

• anxiety
• frightening hallucinations
• paranoid delusions
• blurred vision
• dilated pupils
• tremor

Toxicology screens (drug testing) done on blood and urine specimens can reveal the presence of many chemicals and drugs in the body. The sensitivity depends upon the substance itself, when the substance was taken, and the testing laboratory. Blood tests are more likely to detect the presence of an abused substance than urine tests, however, urine drug screens are more frequently done.

Opiates and narcotics are usually present in the urine 12 to 36 hours after the last use, depending on the amount used and the frequency.

CNS stimulants such as cocaine can be detected in urine anywhere between 1 to 12 days, again depending in frequency of use.

CNS depressants such as Valium and Xanax are detected up to 7 days after the last day of use, mostly depending on the substance used and how quickly it is eliminated by the body (half-life).

Most hallucinogens are also detectable in the urine up to 7 days after the last use. However, cannabis can be detected up to 28 days in regular users.