Drugs are widely available, and trends suggest that the number and type of drugs are expanding. The most harmful drugs are increasingly being made available from diverted legal sources, such as pharmaceutical sources. These, along with clandestine manufactured drugs (i.e. methamphetamine), make up a significant part of our total illegal drug market, and represent the greatest societal harm – particularly when they are injected.

In this discussion New Zealand and international literature are contrasted. Often the effects of the problems associated to injecting drugs are bigger in other countries, which is primarily due to the size and concentration of their populations (i.e. Sydney, Edinburgh, San Francisco, and London). The consequences of injecting drug use, nonetheless, remain similar across these samples. For New Zealand, however, geographical and population spread means the numbers presenting to services are few and far between, which complicates health services and a public health response.


The (mis)use of drugs by way of injection holds numerous risks and costs to the individual, society and public health. This includes for example:

  • people not taking a dose as prescribed under the care of a medical professional and the potential for them to experience variable plasma levels of the active ingredients;
  • the increased risk of overdose, the consequence of the (mis)use of combinations of drugs (especially sedating drugs), especially in people who have little or no tolerance to such drug substances;
  • the consequences of poly-pharmacy (or poly-drug use), which concerns the interaction of drug substances, a result of the consumption of un-prescribed medicines and other drugs or pharmaceuticals.

Drugs of all kinds are being injected and in a variety of ways, including via the veins (the arm, the groin and neck), fatty tissue (the stomach and ‘love handles’) and muscle (leg and arm). Little data is available here in New Zealand describing the IDU injection sites, however. For the injection of drugs specifically, associated risks include:

  • thrombophlebitis,
  • infections from bacteria and fungi,
  • the blockage of small veins and arteries with pieces of tablets or organic substances (causing microvascular blockage), and
  • blood-borne viral infection from shared injecting equipment or the result of poor environmental cleanliness.

While many drug types are injected, diverted pharmaceutical drugs constitute the majority of the controlled substances injected in New Zealand. A diverted pharmaceutical drug for use by injection includes both those drugs sourced legally and illegally, either from prescription or other sources and used for a purpose other than that which was intended. The source of diverted pharmaceutical drugs includes several potential avenues, including:

  • illegal importation;
  • Dr shopping and diversion;
  • A&E and after-hours medical centres;
  • improper prescribing and excessive prescribing;
  • old or excess medicines in the home; theft from palliative care, pharmacies and vets etc;
  • home-bake chemists
  • clandestine manufactured drugs, including methamphetamine, and
  • illegally sourced anabolic steroids contribute markedly to the overall situation.

The diversion of pharmaceuticals and their non-medical use by injection has been described in various settings (here and internationally). The risks associated with the use of drugs in this way, particularly the opioids, is increasingly a worldwide concern. There is already evidence of a high demand for, and supply of, pharmaceutical formulations in Oceania, Europe, South and South East Asia, and North America. The UN has been challenged by NGO’s in recent times to free up the availability of ‘pain drugs’ in particular, it is evident that the consequences of that have not been thoroughly thought through.

Few drugs, particularly those used recreationally, are taken in their pure state. Most drugs substances are mixed with other, often inert, substances (additives) to create a manageable dosage unit and frequently as a result of attempts to maximise revenue from their sale. The additives in pharmaceutical preparations are termed ‘excipients’. These are consistent, sterile components used as forming and binding agents, and include talc, magnesium stearate, and others. For illegally prepared drugs the ‘cutting agents’ or ‘adulterants’ included are wide and varied.

In this environment, the needle exchange programme (NEP) is charged with the provision of sterile injecting equipment. Their primary aim is to prevent the continued transmission of blood borne disease amongst people who inject drugs. While the NEP has limited HIV transmission, other viral transmission, (such as HCV), poor health, and the complications of injecting non-sterile solutions continue to afflict the injecting population.