Heroin - Routes of Administration

Routes of Administration

The onset of heroin's effects depends upon the route of administration. Studies have shown that the subjective pleasure of drug use (the reinforcing component of addiction) is proportional to the rate at which the blood level of the drug increases. Intravenous injection is the fastest route of drug administration, causing blood concentrations to rise the most quickly, followed by smoking, suppository (anal or vaginal insertion), insufflation (snorting), and ingestion (swallowing).

Ingestion does not produce a rush as forerunner to the high experienced with the use of heroin, which is most pronounced with intravenous use. While the onset of the rush induced by injection can occur in as little as a few seconds, the oral route of administration requires approximately half an hour before the high sets in. Thus, with both higher the dosage of heroin used and faster the route of administration used, the higher potential risk for psychological addiction.

Large doses of heroin can cause fatal respiratory depression, and the drug has been used for suicide or as a murder weapon. The serial killer Dr Harold Shipman used diamorphine on his victims, and the subsequent "Shipman Inquiry" led to a tightening of the regulations surrounding the storage, prescribing and destruction of controlled drugs in the UK. Dr John Bodkin Adams (see his victim Edith Alice Morrell) is also known to have used heroin as a murder weapon.

Because significant tolerance to respiratory depression develops quickly with continued use and is lost just as quickly during withdrawal, it is often difficult to determine whether a heroin lethal overdose was accidental, suicide or homicide. Examples include the overdose deaths of Sid Vicious, Janis Joplin, Tim Buckley, Layne Staley, Bradley Nowell, Ted Binion, and River Phoenix.

Chronic use of heroin and other opioids, has been shown to be a potential cause of hyponatremia, resultant because of excess vasopressin secretion.