Australian Institute of Criminology

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Pharmaceutical drugs may be obtained either by prescription or over the counter from pharmacies for legitimate medical purposes. Users of other illicit drugs may utilise pharmaceuticals to supplement their illicit drug use or to reduce their effects.

The most common pharmaceutical drugs diverted for illicit personal use are benzodiazepines and opiate-based drugs. Other drugs may be obtained as precursors or ingredients for other substances such as amphetamines.

Benzodiazepines are designed to reduce anxiety and to help people sleep. They are prescribed to treat epilepsy, as muscle relaxants and to help people withdrawing from alcohol. They may be in tablet, capsule or liquid form.

Opiate based drugs include morphine, codeine and methadone. These drugs are used to treat pain or to reduce the effects of heroin withdrawal. They may be in tablet, capsule or liquid form.

Benzodiazepines are classified as sedatives and anxiolytics. They slow the activity of the central nervous system, making users feel calmer and lethargic, and relaxing muscles. Larger doses may lead to confusion, poor coordination and memory loss.

Long-term use can result in lethargy and a lack of motivation, though some become anxious and aggressive. Tolerance develops very quickly and withdrawal from dependent use can lead to panic attacks, vomiting, depression and paranoia.

Some people use benzodiazepines in combination with other drugs. For example, heroin users may use benzodiazepines to magnify the effects of heroin, when they are unable to source any heroin, or when trying to get off heroin. Users of amphetamines or ecstasy may also use them when 'coming down from a high' to assist with sleep.

Opiate based drugs are depressants, slowing the activity of the central nervous system. Some of the effects of this class of drugs include lethargy, nausea, euphoria, vomiting and shallow breathing. Use of drugs such as methadone with heroin significantly increases the risk of overdose.

Prescription drugs are usually taken orally as a tablet, capsule or liquid. They can be injected intravenously.

The supply of pharmaceuticals is strictly controlled. The most commonly abused drugs are only available on prescription from a medical practitioner or dentist. The importation, supply and manufacture of pharmaceuticals without authority is illegal throughout Australia.

The use of stolen or forged prescriptions to obtain pharmaceuticals is illegal throughout Australia.

The misuse of pharmaceuticals is frequent amongst users of other illicit drugs, particularly heroin and to a lesser extent, amphetamines. One Australian study found that over 50% of intravenous drug users also used benzodiazepines. In a 2004 survey, one in twenty-five (3.8%) people indicated using pain-killers, tranquilisers, barbiturates and/or steroids for non-medical purposes in the previous 12 months.

The demand for pharmaceuticals is linked to the availability of other drugs, especially heroin.

Pharmaceuticals may be known by a variety of trade names or a shortened version of these names. Some common street names for benzodiazepines include benzos, tranks or sleepers.