High dosage can cause rapid or irregular heartbeat, tremors, loss of motor skills and even physical collapse. Long-term use of higher doses can produce amphetamine psychosis which includes hallucinations, delusions and paranoia. Depressants Barbiturates and benzodiazepines are two of the most commonly used groups of these drugs. These drugs are frequently used for medical purposes to relieve anxiety and to induce sleep. Physical and psychological dependence can occur if the drugs are used for longer periods of time at higher doses.
Benzodiazepine use can cause slurred speech, disorientation and lack of coordination.
If taken with alcohol, abuse can lead to a coma and possible death. Narcotics Narcotics include heroin, methadone, morphine, codeine and opium. After an initial feeling of euphoria, usage causes drowsiness, nausea and vomiting. Effects of overdose include slow and shallow breathing, clammy skin, convulsions, coma and possible death. Physical and psychological dependence is high and severe withdrawal symptoms include watery eyes, runny nose, loss of appetite, irritability, tremors, panic, cramps, nausea, chills and sweating.