Heroin administration routes

Brugal MT, Barrio G, De LF, Regidor E, Royuela L, Suelves JM. Factors associated with non-fatal heroin overdose assessing the effect of frequency and route of heroin administration. Addiction 2002 97(3) 319-27. 

Abuse of phencyclidine hydrochloride (PCP) is a national problem that has reached epidemic proportions in urban areas of the United States. The drug is inexpensive, readily obtainable, and is usually used in combination with other drugs such as marijuana, heroin, cocaine, and alcohol (Golden et al. 1982). The routes of PCP use include inhalation, ingestion and parenteral administration. 

Opioids are administered in several ways. Opium was most commonly taken recreationally by smoking, but intravenous administration has become most common since the isolation of opium alkaloids and invention of the hypodermic needle. The development of heroin from morphine at the turn of the twentieth century led to more intense euphoric effects and greater risk for addiction. Heroin may also be snorted, or it can be smoked when added to a medium such as tobacco. Medically, opioids are commonly given through oral, subcutaneous, intravenous, transdermal, or rectal routes. 

In opiate abuse, smack ( junk, jazz, stuff, China white mostly heroin) is self administered by injection ( mainUning ) so as to avoid first-pass metabolism and to achieve a faster rise in brain concentration. Evidently, psychic effects ( kick, buzz, rush ) are especially intense with this route of administration. The user may also resort to other more unusual routes opium can be smoked, and heroin can be taken as snuff (B). 

Pharmacokinetics plays a very important role in the manner in which opioids are abused. Morphine and many of its derivatives are slowly and erratically absorbed after oral administration, which makes this route suitable for long-term management of pain but not for producing euphoria. In addition, opioids undergo considerable first-pass metabolism, which accounts for their low potency after oral administration. Heroin is more potent than morphine, although its effects arise primarily from metabolism to morphine. The potency difference is attributed to heroin s greater membrane permeability and resultant increased absorption into the brain. 

Ross J, Darke S Hall W (1997). Transitions between routes of benzodiazepine administration among heroin users in Sydney. Addiction, 92, 697-705... 

Smolka M, Schmidt LG. The influence of heroin dose and route of administration on the severity of the opiate withdrawal syndrome. Addiction 1999 94(8) 1191-8. 

Abuse potential of a drug is related to its capacity to produce immediate satisfaction, which may be a feature of the drug itself (amfetamine and heroin give rapid effect while tricyclic antidepressants do not) and its route of administration in descending order inhalation/i.v. i.m./s.c. oral. 

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