Drug injection taking drugs, injection is favoured by some people as the full effects of the drug are experienced very quickly, typically in five to ten seconds. It also bypasses first-pass metabolism in the liver, resulting in higher bioavailability and efficiency for many drugs (such as morphine or diacetylmorphine/heroin; roughly two-thirds of which is destroyed in the liver when consumed orally) than oral ingestion would. The effect is that the person gets a stronger (yet shorter-acting) effect from the same amount of the drug. Drug injection is therefore often related to substance dependence. In a recreational context, the shorter, more intense "high"
Drug Recognition Expert categories of classifications a DRE is looking for, including; central nervous system depressants (benzodiazepines), CNS stimulants (methamphetamine), dissociative anesthetics (PCP), cannabis, hallucinogens (mushrooms), inhalants (glue), and narcotic analgesics (opiates). DREs often testify in court, where the term "expert" has important legal implications. Some jurisdictions do not allow the term Drug Recognition "Expert." In these jurisdictions DREs are called Drug Recognition Evaluators, or Drug Recognition Technicians. The acronym 'DRE' has been used to refer not just to the DRE officers, but also to the examination they perform, the "Drug Recognition Examination", or "Drug Recognition Evaluation." The confluence of acronyms leads to