Heroin

Heroin (INN: diacetylmorphine, BAN: diamorphine) is a semi-synthetic opioid synthesized from morphine, a derivative of the opium poppy. It is the 3,6-diacetyl ester of morphine (hence diacetylmorphine). The white crystalline form is commonly the hydrochloride salt diacetylmorphine hydrochloride, however heroin freebase may also appear as a white powder in stead of the street brown powder. See also heroin use.

As with other opiates, heroin is used both as a pain-killer and a recreational drug. Frequent administration quickly leads to tolerance and dependence and has a very high potential for addiction. If sustained use of heroin for as little as three days is stopped abruptly, withdrawal symptoms can appear. This is much quicker than other common opioids such as oxycodone and hydrocodone.

One of the most common methods of heroin use is via intravenous injection (typically known as "shooting up"). If taken orally, heroin undergoes extensive first-pass metabolism via deacetylation, making it a prodrug for the systemic delivery of morphine. When the drug is injected, however, it avoids this first-pass effect, very rapidly crossing the blood-brain barrier due to the presence of the acetyl groups, which render it much more lipid-soluble than morphine itself. Once in the brain, it is deacetylated into 3- and 6-monoacetylmorphine and morphine, which bind to µ-opioid receptors resulting in intense euphoria, decreased pain perception, and anxiolytic effects (relief of anxiety).

Internationally, heroin is controlled under Schedules I and IV of the Single Convention on Narcotic Drugs. It is illegal to manufacture, possess, or sell heroin in Belgium, Denmark, Germany, the Netherlands, the United States, Australia, Canada Ireland, United Kingdom and Swaziland. However, under the name diamorphine, heroin is a legal prescription drug in the United Kingdom, and in the Netherlands, heroin is available for prescription as the generic drug diacetylmorfine to long-term heroin addicts. Popular street names for heroin include black tar, smack, junk, skag, horse, diesel, dope, chaw, chiva, dust and others.

Usage and effects

  • Indicated for: Relief of Extreme Pain
  • Recreational uses: Euphoria, Relaxation
  • Other uses: Pain relief, Cough suppressant, Anti-diarrhea
  • Contraindications: Alcohol, Barbiturates and Benzodiazepines, Stimulants, Other opioids (depends heavily on tolerance)

Side effects

  • Severe: Respiratory arrest, coma, death
  • Central nervous system: Drowsiness, Disorientation, Delirium
  • Cardiovascular & Respiratory: Lowered heart rate, Weak pulse, Hypotension, Hypoventilation, Shallow breathing, Respiratory depression
  • Eyes, Ears, nose, and mouth: Dry mouth, Pupil constriction ("pinpoint pupils"), Miosis
  • Gastrointestinal: Nausea, Vomiting (protracted), Constipation, Dyspepsia
  • Urinary System: Urinary retention
  • Musculoskeletal: Analgesia, Ataxia, Muscle spasticity
  • Neurological: Analgesia, Physical dependence
  • Psychological: Anxiolysis, Confusion, Euphoria, Psychological dependence, Somnolence
  • Skin: Itching, Flushing/Rash

Recreational use of Heroin

Heroin is used as a recreational drug for the profound relaxation and intense euphoria it produces, although the latter effect diminishes with increased tolerance. Its popularity with recreational drug users, compared to morphine, reportedly stems from its perceived different effects. However, this perception is not supported by the results of clinical research studies. In controlled studies comparing the physiological and subjective effects of injected malpheasant heroin and morphine in individuals formerly addicted to opiates, subjects showed no preference for either drug. Equipotent, injected doses had comparable action courses, with no difference in their ability to induce euphoria, ambition, nervousness, relaxation, drowsiness, or sleepiness. Data acquired from short-term addiction studies did not indicate that heroin tolerance develops more rapidly than tolerance to morphine. The findings have been discussed in relation to the physicochemical properties of heroin and morphine and the metabolism of heroin. When compared to other opioids — hydromorphone, fentanyl, oxycodone, and (pethidine / meperidine), former addicts showed a strong preference for heroin and morphine, suggesting that heroin and morphine are particularly susceptible to abuse and addiction. Morphine and heroin were also much more likely to produce euphoria, and other subjective effects when compared to most opioid analgesics. Heroin can be administered several ways, including snorting and injection, and may be smoked by inhaling its vapors when heated, i.e. "chasing the dragon."

Some users mix heroin with cocaine in a "speedball" or "snowball" combination that usually is injected intravenously, smoked, or snorted, producing a more intense rush than heroin alone, but is more dangerous because the combination of the short-acting stimulant with the longer-acting depressant increases the risk of seizure, or overdose with one or both drugs.

Once in the brain, heroin is rapidly metabolized to 6-acetylmorphine and morphine by removal of the acetyl groups and thus serves as a prodrug. Morphine is unable to cross the blood-brain barrier as quickly as heroin, which gives heroin a comparably shorter onset of action. In either case, morphine binds to opioid receptors to induce the opioid high.

The onset of heroin's effects depends upon the route of administration. Orally, heroin is completely metabolized in vivo to morphine before crossing the blood-brain barrier; the effects are the same as with oral morphine. Snorting results in an onset within 3 to 5 minutes; smoking results in an almost immediate effect that builds in intensity; intravenous injection induces a rush and euphoria usually taking effect within 30 seconds; intramuscular and subcutaneous injection take effect within 3 to 5 minutes.

Heroin is metabolized into morphine, a opioid receptor agonist. It acts on endogenous µ-opioid receptors that are present throughout the brain, spinal cord and gut in all mammals. The opioid receptor also binds endogenous opioid peptides such as endorphin, Leu-enkephalin, and Met-enkephalin. Repeated use of heroin results in a number of physiological changes, including decreases in the number of opioid receptors. These physiological alterations lead to tolerance and dependence, and the cessation of heroin use results in a set of extremely uncomfortable symptoms including pain, anxiety, muscle spasms, and insomnia called the opiate withdrawal syndrome. It has an onset 6 to 8 hours after the last dose of heroin. Morphine also binds to opioid receptors. There has also been some controversy regarding whether heroin binds to a subtype of opioid receptors that is not targeted by morphine but is activated by the morphine metabolite morphine-glucuronide.

The heroin dose used for recreational purposes depends strongly on the frequency of use. A first-time user typically ingests between 5 and 20 mg of heroin, but an individual who is heavily dependent on the drug may require several hundred mg per day.

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 it on his victims as did Dr John Bodkin Adams. 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 death was an accident, suicide or murder. Examples include the overdose deaths of Sid Vicious, Janis Joplin, Tim Buckley, Layne Staley, and Bradley Nowell.

Medical help

In situations where the addictive quality is judged to be of lower consequence than other measures (such as cases of terminal illness) diamorphine is a valuable drug. The slow and often very painful end to a cancer sufferer's life can be greatly relieved by the careful use of diamorphine to relieve the pain and worry. In this situation the drug can allow a sufferer to live their last few weeks more actively and independently than would otherwise be possible. Please contact Teen Challenge if you need help with a heroin addiction as we can take you into one of our rehab centers here.