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| Journal of the New Zealand Medical Association,
12-March-2004, Vol 117 No 1190
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Patterns of amphetamine use in New Zealand: findings from the
2001 National Drug Survey
Chris Wilkins, Megan Pledger, Krishna Bhatta, and Sally
Casswell
New Zealand has recently experienced a rapid rise in the use
and manufacture of powerful amphetamines, such as
methamphetamine.1–3 Anecdotally, the rise
in amphetamine use in New Zealand has been implicated in increases in hospital
admissions for drug-induced psychosis,4
increases in street robbery and car
conversion,5 and increases in violent
crime.5 While these consequences are consistent
with the experience of increased amphetamine use
elsewhere,6,7 statistics on criminal offending
and hospital admissions in New Zealand do not routinely record the drug type
involved in an incident and so it has been impossible to precisely measure the
impact of increased amphetamine use. Understanding the implications of growing
amphetamine use is further complicated by the time lag of 12 to 18 months, which
is commonly experienced by users between initial use and progression to
problematic use.8,9
Overseas, clinical research on
amphetamines,9,10 and studies of amphetamine
users,11–14 have identified the central
role that the route and pattern of amphetamine-use plays in the risk of users
experiencing serious problems. Hall and Hando found that amphetamine users
reporting intravenous administration,11 using
twice-a-week or more, and using more than half a street gram in a single session
were more likely to experience adverse psychological effects, dependency, and
report violent offences. Other studies have noted a link between the increased
use of amphetamines by young people, and rises in intravenous drug use by these
age groups, suggesting this is a response by some amphetamine users to growing
tolerance.15–18 Studies elsewhere have
also found amphetamine users to be extensive poly drug
users.11,14,16,19,20 Other stimulant type
drugs, such as cocaine, were commonly used in combination with amphetamines,
while opioids and tranquillisers were used to self medicate against adverse side
effects. This poly drug use increased the likelihood of users experiencing
problems.19,21,22
This paper presents findings from the 2001 National Drug
Survey on the patterns of amphetamine use in New Zealand. Data is presented on
the frequency and amount of amphetamine used, and the extent of poly drug use
and intravenous drug use by amphetamine users.
MethodsIn 2001, using a Computer
Assisted Telephone Interview (CATI) system, a national sample of approximately
5500 people aged 15–45 were interviewed about their recreational drug use.
Telephone numbers were selected using a stratified random digit dialling method
so that each household (of a particular stratum) nationwide had an equal chance
of being called. In order to represent the different socioeconomic
characteristics of the population, the country was divided into 33 strata. A
proportionate sample from each stratum was then taken. Within each household,
one person was randomly selected for an interview. The sample was weighted to
adjust for household size. Interviewers received intensive training at the
beginning of the survey, and a supervisor was present at each shift to monitor
the quality and consistency of interviewing and to handle any problems. Each
telephone was tried at least 10 times in an effort to reach those persons seldom
at home. An 80% response rate was achieved. Further details of the methodology
can be found in Wilkins et al.23
Respondents were asked about their use of alcohol,
tobacco, cannabis—and 22 other drug types, such as cocaine, crack, heroin,
and LSD. The amphetamine drugs were referred to by the broad term
‘stimulants’, which the interviewer described as meaning
‘uppers, speed, amphetamine, and methamphetamine’. Respondents were
asked about use of other stimulant-type drugs, such as cocaine, crack cocaine,
and ice (ie, crystal methamphetamine), in separate questions of the
interview.
Those persons who had used stimulants in the last year
were asked a range of additional questions about their patterns of use,
including how many times they had used stimulants in the last year, and the
quantity of stimulant they used on a ‘typical occasion’.
Anecdotally, the quantities of amphetamine most commonly used in New Zealand
were lines, points (approximately 0.1 gram) and grams of powder. The quantity
question included coded amounts from 0.1 gram up to 28 grams. The equivalent
amount in lines and points was included in brackets next to the appropriate
quantity to facilitate the identification of the amount typically used.
Respondents could also indicate if they only used ‘pills/tablets’ or
‘liquid’ amphetamine.
In a separate section of the interview, respondents
were asked if they had ever used a needle to inject drugs for recreational
purposes and how many times they had done so in the last year. Respondents were
not asked directly what drug types they had injected. However, the drug types
used by a respondent could be identified from other parts of the interview, and
the injectable drugs are essentially limited to the opioids and amphetamines.
What is reported is intravenous drug use by amphetamine users rather than
intravenous amphetamine use. The confidence levels reported are at the 95%
level.
ResultsPrevalence
Overall, 5.0% (4.3–5.7) of the sample had used stimulants (uppers, speed,
amphetamine, methamphetamine) in the last year (n = 275). Users were
overwhelming male (70%) and in the 18–29 year old age groups (Figure 1).
For males, 5.7% (2.4–9.0) aged 15–17 years, 15.0% (8.7–21.2)
aged 18–19 years, 12.3% (8.8–15.9) aged 20–24 years, and 11.3%
(7.8–14.7) aged 25–29 years had used stimulants in the last
year.
Figure 1. Last-year use of stimulants (by gender and
age group) 2001
 Frequency of use
Fifty-three percent of last-year stimulant users had used these drugs 1-2 times
in the last year (Figure 2). A further 20.1% had used them 3-5 times in the last
year. The other frequencies of use reported in the last year were 7.7% using
10-19 times (about once every month), 3.1% using 50-59 times (about
once-a-week), and 1.0% using 100-109 times (about twice-a-week). Only 0.2% of
last-year users said they used stimulants 350-359 times in the last year (about
daily).
Figure 2. Frequency of use of stimulants in the last 12
months, 2001
 Quantity used About
7% (6.8%) of last-year stimulant users indicated they only used pills/tablets of
amphetamine. No respondents reported only using liquid amphetamine.
Of those users who used powder amphetamine (93.2% of all
users), the most popular amount used on a typical occasion was one line (0.1
gram) [32.3%], followed by two lines (0.2 gram) [27.7%], and five lines (0.5
gram) [13.3%], respectively (Figure 3). Five percent of last-year users used 1
gram of stimulants on a typical occasion.
Figure 3. Amount* of stimulant used on a typical
occasion, 2001
 *For those users who did not consume pills or
liquid
Poly drug use The
other drug types most commonly used in the last year by stimulant users were
alcohol (92.5%), cannabis (85.7%), tobacco (72.6%), skunkweed [hydroponic
cannabis] (65.8%), LSD (44.7%), ecstasy (43.4%), magic mushrooms (26.5%), ice
[crystal methamphetamine] (15.0%), rush [amyl nitrate, butyl nitrate] (14.3%),
kava (12.8%), GHB [gamma-hydroxybuterate] (10.6%), cocaine (9.3%), and ketamine
(9.1%); see Table 1. Last-year stimulant users had tried an average of 8.5 drug
types ever (range 1–20, SD 3.3), used an average of 6.4 drug types in the
last year (range 1–17, SD 2.8), and used an average of 4.2 drug types in
the last 30 days (range 0–13, SD 2.1).
Table 1. Percentage of last-year users of stimulants
who used other drugs in the last 12 months,
2001 (click
here to view)
Last-year needle use
A total of 0.2% (0.1– 0.3) of the whole sample (11 people in the
weighted survey but 13 respondents) had used a needle to inject a drug in the
last year. Seventy-seven percent of these last-year needle users also used one
of the opioid drugs in the last year (ie, heroin, homebake, morphine, poppies,
other opiates). Sixty-eight percent of last-year needle users also used
stimulants.
DiscussionDue to the difficulties of surveying
illicit drug users,24 particularly heavy drug
users,25 the National Drug Survey is likely to
under estimate the true number of users. However, well designed CATI surveys
with high response rates have been found to produce similar results to other
population survey methodologies.26 The findings
presented here are best thought of as providing reliable but conservative
estimates of illicit drug use in New Zealand.
The National Drug Survey provides a broad representative
picture of the amphetamine using population in New Zealand, including
experimental and occasional users. However, the household sample frame may mean
that some heavy problematic users who are living on the streets or living
particularly erratic lifestyles are missed. This limitation is likely to be
particularly relevant with respect to reaching intravenous drug users who are
often heavy drug users.
Amphetamine drugs come in varying levels of potency and
purity and the strength of amphetamine plays an important role in the risk of
experiencing problems. At present the understanding of the strength of the
amphetamines being used in New Zealand is largely anecdotal. Seizures of
amphetamine in New Zealand are not routinely tested by the authorities for
purity levels as this information is not generally central to achieving a
prosecution. Approximating the strength of the amphetamines used is made
difficult by the different slang names which are developed to identify different
types of amphetamine, such as the term ‘pure’ in New Zealand, the
loose way these street terms are used by drug dealers and drug users, and the
varying ability of users to accurately assess the potency of the drugs they are
using depending on their level of knowledge and experience.
Drawing on existing sources, including social histories of
amphetamine use,27 recent analysis of the
amphetamine situation in Australia28 and
reports of amphetamine seizures in New
Zealand,1–2,29 it is possible to identify
four broad types of amphetamine being used in New Zealand: amphetamine sulphate;
methamphetamine powder; ‘pure’ methamphetamine; and ice or crystal
methamphetamine. Amphetamine sulphates include diet pills and common
prescription medicines, which may have been illegally obtained from legitimate
dispensing sources. Methamphetamine is a particularly powerful type of
amphetamine.28 In the powder form, it is
usually heavily cut with adulterants. The New Zealand Customs Service reports
the normal purity of methamphetamine powder at street level in New Zealand is
between 5%–15%.29 Methamphetamine powder
is purchased by the gram or ounce and is consumed in lines of powder.
‘Pure’ is high-potency uncut methamphetamine and is sold by the
point (0.1 gram). A point of ‘pure’ is sufficient for a number of
doses. Ice or crystal methamphetamine is high-potency crystallised
methamphetamine and is generally manufactured and imported from Asia. It is not
entirely clear (at present) how different the New Zealand manufactured
‘pure’ is from the Asian crystal methamphetamine.
Several limitations with the National Drug Survey data from
the perspective of estimating the level of heavy amphetamine use in New Zealand
must be acknowledged The questions in the National Drug Survey about the
quantity of stimulants used referred to use on a ‘typical occasion’
only. This may not fully capture amphetamine consumption patterns that can
sometimes include binge use, where a user consumes large amounts of the drug
over several hours or days.10 This type of use
greatly increases the risk of problems such as psychosis.
Second, stimulant users in the National Drug Survey were not
asked directly whether they used a needle to inject stimulants and this would
have provided a clearer picture concerning the level of intravenous amphetamine
use as opposed to merely amphetamine use by intravenous drug users. However, the
fact that an amphetamine user is also using a needle to inject other drugs
suggests that the injection of amphetamine, if not already occurring, may be a
future option as tolerance develops.
With these limitations in mind, several key points about
patterns of amphetamine use in New Zealand can be drawn from the data. Over 10%
of New Zealand men aged 18–29, the highest using group, had used
amphetamines in the previous year in 2001. Many last-year users used
amphetamines fairly infrequently—ie, 73% used them five times or less in
the previous year. However, while many users also used fairly low doses, 22%
used 0.5 gram (or more) of amphetamine on a typical occasion. Poly drug use was
common within the amphetamine-using population with the use of a range of
illicit drug types at levels many times higher than that of the general
population. Of particular concern were the relatively high levels of the use of
LSD, ecstasy, cocaine, homebake heroin and intravenous drug use among
amphetamine users compared to the general population.
Most of the needle-using amphetamine users also used
opioids. It may be the case they are primarily opioid users. Australian research
has found that opioid users will switch to other illicit drug types such as
cocaine and amphetamines when heroin is in short
supply.30 Opioid users in New Zealand may be
simply responding to the recent greater availability of high potency amphetamine
relative to the traditional supply of opioids. The small number of intravenous
drug users in the National Drug Survey sample makes further analysis
problematic. Close monitoring of intravenous drug use within the
amphetamine-using population is required in New Zealand to ensure increased
amphetamine use is not fuelling increases in intravenous drug use. Other
research methodologies than the household population approach used in the
National Drug Survey may be more suited to achieving this task.
The infrequency of amphetamine use in New Zealand could be
explained by several factors—including the cultural context of its use
(ie, it is still being limited to infrequent large dance party events), the
‘newness’ of the drug, the immaturity of domestic production and
supply networks, and/or the effectiveness of police enforcement. Exploring these
reasons is beyond the scope of this present paper. However, it interesting to
note that the price of amphetamine in New Zealand is higher than in Australia
with 1 gram selling for $100-$180 in New Zealand compared to $59-$118 in
Australia (based on prices reported in the Illicit Drug Reporting System of
$50-$100,20 and a ‘New Zealand dollar to
Australian dollar’ exchange rate of 0.85).31
Unfortunately, the price in New Zealand is believed to have fallen
dramatically since the establishment of large-scale domestic manufacture in the
late 1990s (from $250–$300 per gram in mid-1999 to $100–$180 after
that time).31 Ongoing competition between
domestic producers may cause this trend to continue (with implications for
frequency of use).
It is also important not to overstate the role that the
route of administration and the pattern of amphetamine-use play in users
experiencing adverse effects. As with all drugs, effects and harms are also
dependent on the user’s physical condition, psychological state of mind,
context of use (eg, at home, at a club, while driving, etc), and whether the
drug was used in combination with other
substances.32 In the case of psycho-stimulants,
heavy long-term use has been associated with increased sensitivity to
dosage.9 Users who have experienced
methamphetamine-induced psychosis have been found to experience relapses of
psychosis after only a small subsequent dose of the drug, or even after exposure
to a stressful situation.33,34
In conclusion, the findings from the 2001 National Drug
Survey indicate there is a substantial minority of amphetamine users in New
Zealand who use quantities of amphetamine in a single session that have been
identified in research elsewhere as
hazardous.11. This is of great concern as high
dosage has been described in the literature as the ‘first stage’ to
other hazardous using patterns, such as intravenous administration and high
frequency use.35 High levels of poly drug use
by amphetamine users indicates users may be at risk of problems from other drug
types or drug types used in combination with amphetamines, and not solely from
amphetamines alone. Ongoing monitoring is required to identify if increased
amphetamine use is a source of increased intravenous drug use.
Author information:
Chris Wilkins, Researcher; Megan Pledger,
Statistician; Krishna Bhatta,
Statistician; and Professor Sally
Casswell, Director, SHORE (Centre for Social and Health Outcomes Research and
Evaluation), Massey University, Auckland
Acknowledgements:
The 2001 National Drug Survey was a project of the Alcohol & Public Health
Research Unit (APHRU) at the University of Auckland, and was funded by the
Health Research Council and the Alcohol Advisory Council of New Zealand. The
funding for our survey was provided by the Health Research Council as an
investigator-initiated grant to Professor Sally Casswell. The project was led by
Dr Chris Wilkins with Rachael Lane, Mary Blade, and Heather Seal. The data
management and statistical analysis were carried out by Dr Krishna Bhatta and Dr
Megan Pledger (assisted by Michael Ford and Alistair Stewart). Lastly, we
acknowledge the time and willingness of the survey respondents without whom the
project could not have taken place.
Correspondence: Dr
Chris Wilkins, SHORE (Centre for Social and Health Outcomes Research and
Evaluation), PO Box 6137, Wellesley Street, Auckland. Fax: (09) 366 5149; email:
c.wilkins@massey.ac.nz
References:
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