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UK Opiate Usage, Consumption, Attitudes, Prices
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UK Opiate Usage

Consumption, Attitudes and Prices

There are many different estimates of the amount of opiates consumed by dependent users. Few of these can be regarded as entirely reliable, as the amounts and purities of the drug seized can vary considerably. Most of the research into opiate consumption in the UK was conducted in the mid-1980s.

Heroin

Consumption - The Literature

In 1987, Parker et al [1] reported that users consumed between 2 "bags" of heroin per day (about £10) and one gram (£60), with the majority consuming between one quarter and one half gram. Caplin & Woodward [2] in a survey of problem drug users conducted by the BBC, found that 39% of the heroin users they surveyed reported spending over £250 per week on the drug. This would have been the rough equivalent of 0.6g of heroin per day (@£60 per gram). The Institute for the study of Drug Dependence (ISDD) [3] suggested that a dependent user is likely to take one quarter gram per day, although they did not state the source from which this estimate is derived.

In 1988, Gossop et al [4] found that, for users of heroin by injection 70% used less than 0.5g per day, 19% used 0.5g-0.75g, and 11% used over 0.75g per day. Two thirds (66%) of chasers (inhalers) used under 0.5g per day, 12% used 0.5g to 0.75g, and 22% used over 0.75g per day. The same team reported in 1992 [5] that current heroin users would consume between 0.06g and 5g per day, with 23% using 1g per day or more. Parry [6] , in criticising maintenance prescribing at levels of 100mg (pharmaceutical diamorphine), suggested that daily prescription of 300-400mg would normally be needed to prevent an addict "topping up" from illicit sources, and that few users would consume more than 500-600mg per day even if free access were allowed. These quantities would be the equivalent of 0.6g-1.8g of street heroin, at 30-50% purity [7] . In an autobiographical account, Stewart [8] stated that addicts will use 'at least £20 to £60 per day (1/4g for £20)', and that some 'users can smoke 2-3 grams a day costing up to £70 each.'

Assessing the actual level of opiate dependence is fraught with difficulties, primarily concerning the perceived reliability of self-report accounts of usage, and the unknown purity levels of street drugs. Higgins et al [9] proposed that testing pupillary response to a challenge dose of methadone would provide an objective marker, as response was lowest in heroin addicts claiming the heaviest and most prolonged levels of dependent use.

Case Histories

I have examined medical reports of a number of registered heroin addicts in the course of court cases, and have noted individuals being prescribed in excess of 300mg of pharmaceutical (injectable) diamorphine per day, equivalent to the amount contained in around a gram of street heroin. Many registered addicts supplement their prescriptions with street heroin, indicating yet higher levels of use.

A recent case involved detailed accounts of an alleged heroin supply conspiracy in the North of England [10] . A total of 782 transactions were recorded, involving a nominal 477.45g and £17,554, over 90 regular customers plus a number of individuals whose name appeared once. The average (mean) deal size was 0.6g, with an average price paid of £22.15. Some customers would purchase small amounts on a regular basis, other customers would buy amounts varying from 0.1g to 1/8oz (3.5g) at different times, presumably according to the funds available. Presuming these records were complete, and represented the only source of heroin for the individuals concerned, the accounts provided a unique insight into the consumption and purchasing patterns of 92 heroin addicts. When all the named individuals and their total purchases were ranked in order, the results were as follows (table 1):

Table 1 - Heroin Use Percentiles
Percentile	10-day Use (g)	Daily Use (mg)	Pure Drug (mg)
Lower 5%	0.2	20	4
Lower 10%	0.3	30	6
Lower 25%	1.2	120	25
Median (50%)	2.8	280	59
Upper 25%	5.15	515	108
Upper 10%	8.95	895	188
Upper 5%	12.25	1225	257
Top 1%	26.7	2670	561

The most common deal sizes were 0.5g for £20 (33% of transactions), followed by 0.1g for £5 (23%), 0.2g for £10 (21%), 1g for £35 (5%), 1/16oz for £60 (6%) and 1/8oz for £110 (3%). The name of the individual who purchased an ounce appeared only once during that period. The median deal size was also 0.5g for £20, although half the total quantity would have been supplied in gram deals or larger. Intermediate deal sizes would typically involve two or more units (e.g. 0.7g = .5 for £20 and .2 for £10), thus each unit of sale had a (more or less) fixed price with no further discount for multiple units.

Valenciano et al [11] found French intravenous heroin users injected an average of 3.6 times per day. Perneger et al [12] , who studied daily drug administration records of 37 patients enrolled in the Geneva heroin maintenance programme, reported "The average dose of intravenous heroin was 466 mg/day; the total opiate dose, after conversion of oral opiates to heroin-equivalents, was 543 mg/day", and concluding" "Heroin users who have facilitated access to legally prescribed drugs consume about 0.5 g heroin per day." Alvarez-Mazariegos et al [13] , studying heroin detox patients in Spain, reported "a daily average of 250 mg per day of heroin (125-1,000 mg)". Mendis [14] reported that among 100 Sri Lankan addicts under treatment "average amount consumed was 340 mg per day.", whereas in India, Adityanjee et al [15] reported "The majority of heroin addicts were under 30 years of age (87.6 per cent), unmarried (67.6 per cent), had reached either high school or college (80.0 per cent) and reported having taken up to one gram per day (56.6 per cent) of the drug for one year or less (63.8 per cent). Heroin was mainly smoked (74.3 per cent) and in some cases inhaled, sniffed or injected." Howe et al [16] , studying withdrawal among addicts in a laboratory setting, reported that subjects had an "average daily intake of approximately 973 mg of 92 - 98% pure heroin before entering the study."

IDMU Surveys

In the 1994-2002 combined IDMU surveys of recreational drug users [17] only 72 individuals reported daily use of heroin out of a total sample of 11652 users of controlled drugs. It is unlikely that the survey - most respondents were recruited at a rural pop festivals - would have provided a representative sample of heroin users, who may have been unable to afford the entrance fee, or unwilling to leave their home area to travel to a place where supplies of the drug would be uncertain and/or expensive. Higher levels of heroin use have been found in samples at free inner-city events.

The average reported monthly cost of heroin for the 159 individuals who reported a positive amount (40 were for £0) was £159.32, for daily users £449.13, although 21x individuals (in the overall sample) spent in excess of £500, and eight over £1000, per month on heroin (max. £4000). The average (including experimental and occasional users) would equate to 1 £10 "bag" every other day, and the heaviest 5% these users would be using 2-3 grams per day (bought at ounce-equivalent prices)-median £50, top 25% £250, to 10% £500, top 5% £1000, top 1% £1400). It is noted that the user rating "marks out of 10" mirrors usage or intended usage (p<.0001), and may represent an crude but useful predictor of usage if included in the context of attitudinal studies.

Fig 1 - Weekly usage & Heroin user-ratings

It would therefore appear that there is a wide variation found in the amount of heroin used daily, from one or two "bags" up to one to two grams of street quality heroin, and that users by inhalation ("tooting"or "chasing the dragon") can require considerably more heroin powder than injectors to achieve the same effect.

Heroin Purities:

It might be assumed that the lower down the distribution chain that Diamorphine is seized, the lower will be the purity [18] . However, the Home Office Forensic Science Service Drugs Intelligence Unit have indicated [19] that there are no consistent differences in purity between heroin seized by the gram and by larger amounts. If anything their results [20] suggest that gram deals tend to be purer than larger quantities, although the low sample sizes would suggest that this apparent trend, at higher levels of the market, is probably spurious. The purities of large customs seizures do not significantly exceed street purities [21] , the quarterly average purities of police and customs seizures of heroin from 1997-2001 [22] . are shown below.

The quarterly average purity figures for heroin powders analysed by the forensic science service in the first quarter of 1996 (the latest figures published) ranged from 44% to 45%, the typical range was last quoted in 1991, and had varied from 25%-55% [23] . Between 1992 and 1997, the average purity of heroin powders varied on a quarterly basis within a range of 35-48% . It is clear that the average purity of heroin powders has risen significantly in recent years.

Seizures analysed at the Wetherby laboratory (North East region) in the first half of 1995 [24] found the average purity to be 41.6% with an average wrap size of 82mg (approx 1/12th gram), in the second half of 1995 the Wetherby figures were 38% average purity and 133mg average wrap size. In a statement produced in a July 1997 case at Mold Crown Court by a Chorley forensic scientist a typical heroin wrap was stated to contain between 100mg and 200mg of powder.

The Home Office disclosed the number and distribution of seizures of heroin at different purity levels, for illicit heroin powders examined by the Forensic Science Service during 1997. These are reproduced in table 3 below:

Table 3 - Heroin Purity Distributions 1997
Heroin purity	Percentage of cases
Less than 5 and 5-10	2
10-20	12
20-30	21
30-40	23
40-50	23
50-60	15
More than 60	5
Police mean 35%	Customs mean 34%

UK Heroin prices

Heroin prices have been relatively stable since 1999, with gram prices typically between £40 and £80, falling from the £70-£90 in previous years.

Table 4 - Heroin Price Trends 1995-2002
Item	1995	1997	1998	1999	2000	2001	2002
Heroin gram Price	£83.33	£69.69	£71.25	£56.40	£60.00	£54.00	£48.54
Subjective rating (0-10)	2.9	2.7	2.2	3.0	2.4	1.8	1.4
No. reporting (heroin)	9	46	48	87	57	19	52
Total Respondents	215	1136	1153	2173	2353	681	2825

Prices of heroin fell significantly between 1995 and 1999, with the 1999-2001 Surveys [26] suggesting heroin prices to be relatively stable, although there is evidence of a slight fall from 2002 results with increasing numbers of respondents reporting gram prices under £40.

The distribution of retail prices from 1995 to 2002 are shown in fig 2 below. The most common "bag" price is overwhelmingly £10, less commonly £20 or £5, grams typically £30-£80, with occasional reports of cheaper or more expensive deals. There is considerable variation in ounce prices.

Fig 3 - Distribution of reported UK Heroin prices (1995-2002)

At retail level, price falls have been reflected in increased purity and in the size of £10 "bags". In court cases involving heroin, typical bag sizes have increased from 80-120mg in the early 1990s, to 150-250mg more recently.

Methadone

Methadone (physeptone) is an opiate drug commonly used to counter the effects of opiate withdrawal syndromes without the euphoriant effects of heroin or morphine. The effects of methadone are longer lasting than for heroin, such that it is common to prescribe a daily dose, whereas a heroin user would need to take the drug every 4-6 hours.

The prescribing of methadone is tightly-regulated, with safeguards to prevent diversion of supplies to the illicit market. For this reason, heroin addicts under treatment are commonly prescribed oral linctus to be taken under supervision by the dispensing chemist or clinic. Only once users have complied with a treatment programme for some time would they normally be allowed more than one days supply at a time.

IDMU surveys

Methadone was included in the list of named drugs in the IDMU survey for the first time in 1999 [27] , and has continued in successive years. A total of 325 respondents (4.0%) had ever used the drug, (based on age of first use responses rather than frequency data) of those 32 used daily - a relatively high proportion, and similar to the incidence of daily heroin use. Only 25x users reported monthly spending, of whom 8 reported "free" (suggesting prescription) and 3 reported spending over £50, the highest at £90 per month, probably reflecting consultation fees for private prescriptions -the majority of daily users receive prescriptions.

The average user-rating of Methadone, 1.46 out of 10, is one of the lowest for any drug. A handful of people gave it a positive rating (fig 4). Only 2% of non-users (but users of other drugs, who expressed a preference) would try the drug if offered, one of the lowest ratios for any drug. It is unlikely that methadone would be sold to, or tried by, any drug users other than heroin addicts or recovering addicts in treatment seeking to self-medicate. As such, the abuse potential of methadone is low.

Fig 4 - Subjective ratings for Methadone

Prescription

Prescribed dosages range from virtually nil up to around 100mg per day, more in special cases, depending on the severity of addiction and stage of treatment (i.e. in a reducing maintenance regime smaller doses are prescribed over time). If too much is prescribed, methadone may be sold on to other users, sometimes with tragic consequences for na"ve users with no tolerance level who may overdose.

The general prescribing practice is to allow the addict the minimum quantity required to stabilise his/her condition - the tendency is to under prescribe. If too little is prescribed, addicts will usually supplement their prescription with street heroin.

Street Prices

I am unaware of any published figures within NCIS or related price lists in respect of methadone.

IDMU Prices - Since 1999, methadone prices have been sought by "dose" and "bottle". Dose prices vary considerably, as there was no standard size unit (linctus being the most common form), with an average of £4.76 (free, £5 or £10 per "dose"-unspecified but approx 30ml, with methadone bottles (100ml) either "free" (prescribed) or most commonly £10 (average £9.84).

Fig 5 - UK Methadone Price distributions 1999-2002

Methadone may be prescribed (either via drugs clinics or privately) to drug users to avoid or ameliorate the symptoms of withdrawal. Prescribed drugs may be "stockpiled" to guard against periods of interrupted heroin supply, or during DIY attempts at withdrawal.

Other Opiates

A range of opiate preparations are available in medical practice, ranging from over the counter painkillers, through prescription only medicines, to powerful preparations only available to treat hospital in-patients. The most common form of pharmaceutical opiates are tablets, although the drugs can also be in oral linctus, or injectable ampoules.

Many heroin addicts will obtain prescribed opiate drugs for periods during which they are unable to obtain heroin, as use of alternative opiates can delay or ameliorate withdrawal symptoms.

The dosages used by opiate-dependent individuals may be several times the maximum recommended daily therapeutic dose.

IDMU Surveys

The overwhelming majority of users of non-prescribed pharmaceutical opiates are also users of heroin. In the 1999-2002 IDMU surveys, 6% of drug users had tried these drugs, among the regular users, as daily users were the smallest group, whereas "regular but not daily" use is the smallest group among users of heroin or methadone-a different pattern consistent with use of these drugs as a "back up" among heroin addicts.

Opiate Tablet Prices

I am unaware of any published figures within NCIS or related price lists in respect of opiate tablets.

Opiates may be prescribed (either via drugs clinics or privately) to drug users to avoid or ameliorate the symptoms of withdrawal. Prescribed drugs may be "stockpiled" to guard against periods of interrupted heroin supply, or during DIY attempts at withdrawal.

Fountain et al [30] described a limited illicit market for diverted prescription drugs, with price dependent on local availability and demand, and on the dosage of each tablet. Dihydrocodeine is reported as being "rarely available", with prices of 3-5 tablets for £1. Fountain et al do not quote a price for methadone tablets, stating they are rarely available. Methadone Linctus sells for £10 per 100mg bottle, a value of 10p per mg. Thus 5mg tablets could be expected to sell for around 50p each. Injectable ampoules attract higher street prices (£4-5 for 10mg, £8-£15 for 50mg) but offer a more efficient route of administration.

Enquiries with drugs workers and researchers, indicated that there is not a general market or recognised street price for such tablets, but that where sold, substitute opiates such as DF118 tablets could vary in price from around 10p up to £2 per tablet, one reported a 60mg morphine continus tablet sold for £1.

IDMU Prices - Since 1999, "other opiates" prices have been sought by units of 1x, 10x and 100x tablets.

In the 1998 IDMU survey, only one user reported use dihydrocodeine tablets out of 1153 respondents, but never quoted a street price. From 1999, "other opiates" were included as named drugs. The most common price both for single and multiple tablets was £5-there are clear differences in the potential prices depending on which opiates/dosages are involved.The distribution of methadone and "other opiate" price from 1999-2002 is shown below:

Fig 6 - UK Other Opiate Price distributions 1999-2002

Opium

Opium is the raw exudate of the opium poppy (Papaver somniferum) which is scraped from the scored seed head of the poppy, which contains a number of alkaloids including morphine and codeine. Opium is most commonly used as a raw material for the extraction of morphine base, which in turn is treated chemically to produce diacetylmorphine (heroin). Opium may be smoked or eaten, but is rarely found within the UK.

There are very few other reports of opium use in the UK or in modern societies. However, medicinal products containing opium were widely available in the UK from the 19th Century and in the UK until the 1960s under trade names such as "Dovers Powders". Dovers Powders were stated to have an active dose of between 1/4 and 1/2 gram of raw opium [31] . The Earl of Mar, who died in 1828, was reported to take 49 grains (3.2 grams) of raw opium per day, users of laudanum were reported to take up to 40 ounces of mixture (2.6g opium) per day. These would represent daily morphine dosages of 104mg (2.6g @ 4%) to 416mg (3.2g @ 13%).

It may be possible, in theory, to extract the morphine base from the opium, and hence produce a quantity of heroin as a result. It would be unreasonable to speculate on a precise potential value of heroin which could be produced from the opium seized in the absence of forensic evidence as to the proportion by weight of the substance attributable to morphine, from which a potential yield and value of heroin could be calculated. In the last century the range of morphine content in opium was 1% to 20% [32] , although 5% to 12% would be typical values.

The US State Department estimated that 570 metric tons of opium produced in South East Asia could yield 57 tons of heroin [33] . On this basis, 1 kilogram of opium would be expected to produce up to 100 grams of heroin. The former Soviet republic of Khirghizistan estimated in 1993 that production of 100 tons of opium, containing approximately 17% morphine, could yield $1 billion in gross revenue. On this basis, 1 kilogram would be worth $10,000 (approx £6500) [34] .

Prevalence

Opium Seizures: There is no significant organised market in raw Opium in the UK. Since 1990, there has been an average of 40 opium seizures per year [35] , mostly from HM Customs, with an average quantity seized of 416 grams per seizure (399 seizures involving 166 kilos over 10 years). In recent years the number of seizures has been falling, although the quantity seized has been increasing. Table 11 shows the number of opium seizures by police and customs since 1990.

IDMU Surveys

In our 1984 survey [36] , 6.7% of a sample of 608 recreational drug users had used the drug on at least one occasion. Use of opium is becoming more common (18% of users in 1998-2000 IDMU surveys), although for the vast majority this involves a single use or on a small number of occasions.

The daily users would be consuming between 0.25 and 2 grams per day, depending on the quantity purchased at any one time, and the price obtained. The heaviest user claimed to be spending £500 per month on Opium.

Fig 8 - Opium Ratings & Usage

It would appear that there are two distinct types of user, the recreational (white) user who would purchase small quantities at high prices, and the regular (ethnic) user who would be able to obtain larger quantities at much reduced prices from within the ethnic community.

Opium Prices

IDMU has been monitoring Opium use and prices since 1998 (until then Opium was a "write-in" option). Price reports range from £2 to £100 per gram (mean price £19.26), and only seven ounce price reports from £15 to £120, a mean price of £71.12 per ounce (excluding two "free" reports). The distribution of 1998-2000 Opium prices is shown in fig 9 below.

Fig 9 - Distribution of UK Opium Prices 1998-2002

Much will depend on the source, e.g. a family or community member from a producer country could expect to pay very much less than a UK-based stranger with no connections. For instance, in Afghanistan a kilo of opium costs around £500 [37] , equivalent to £14 per ounce, and may be expected to contain up to 10% morphine by weight.

There are a limited number of "official" reports of opium prices, including £10 per gram - London Sept 1996 [38] , £10,000 per kilo (no local gram prices) in December 1997 [39] , and £250-£300 per ounce (Manchester 1996) [40] .

Conclusions

Heroin

Whereas with most drugs there is a "pyramid" of usage, with progressively fewer experimental, occasional, regular and daily users, with heroin daily users outnumber those who use regularly but not daily. Only a small proportion of those who experiment with heroin, or use the drug occasionally, become addicted, although the risk of dependency increases sharply when heroin is used weekly or more often.

Monthly spending on heroin, naturally, increases with frequency of use, although a minority of heroin users are able to estimate their spending on or quantity of the drug used. The average reported monthly cost of heroin for daily users £449.13. The overall average (including experimental and occasional users) would equate to 1 £10 "bag" every other day, and the heaviest 5% of users would be using 2-3 grams per day, purchasing in fractions of ounces rather than "bags" or gram deals.

In detailed accounts seized as part of police investigations into a supply conspiracy in 2000/01, the most common deal sizes were 0.5g for £20. Each unit of sale had a (more or less) fixed price with no further discount for multiple units.

User ratings "marks out of 10" reflect and may predict usage or intended usage and may represent an crude but useful predictor of usage/prevalence if included in the context of attitudinal studies in the general population. User ratings for heroin have been falling throughout the period of the surveys.

Heroin prices have been relatively stable since 1999, with recent gram prices typically between £30 and £60, falling from £70-£90 in previous years. At retail level, price falls have been reflected in increased purity and in the size of £10 "bags". In court cases involving heroin, typical bag sizes have increased from 80-120mg in the early 1990s, to 150-250mg more recently.

Methadone

The average user-rating of Methadone, 1.46 out of 10, is one of the lowest for any drug. Only a handful of respondents gave it a positive rating. Only 2% of non-users (but users of other drugs, who expressed a preference) would try the drug if offered, one of the lowest ratios for any drug. It is unlikely that methadone would be sold to, or tried by, any drug users other than heroin addicts or recovering addicts in treatment seeking to self-medicate. As such, the abuse potential of methadone, other than in pre-existing opiate users, is low.

Average "street" price of methadone bottles (100ml) either "free" (prescribed) or most commonly £10 (average £9.84).

Many registered addicts supplement their prescriptions with street heroin, indicating that many prescribed dosages may be too low to stabilise use, but also may reflect a desire for the high provided by heroin but not methadone.

Other Opiates

The most common price both for single and multiple tablets was £5-there are clear differences in the potential prices depending on which opiates/dosages are involved.

Prescribed drugs may be "stockpiled" to guard against periods of interrupted heroin supply, or during DIY attempts at withdrawal.

Opium

In our 1984 survey [41] , 6.7% of a sample of 608 recreational drug users had used the drug on at least one occasion (as write-in option). Use of opium is becoming more common (18% of users in 1998-2000 IDMU surveys), although for the vast majority this involves a single use or on a small number of occasions.

User-ratings for opium are much higher than for other opiates, particularly among non-users, and the "willing to try" ratio (31.1%) is much higher than for heroin (9.1%), methadone (2.5%) or other opiates (11.9%), again ratings tend to predict intention to use or levels of use. Consequently, should Opium become more widely available in the UK, it could find a ready market beyond those individuals who are already users of heroin or other opiates.

It would appear that there are two distinct types of user, the recreational (white) user who would purchase small quantities at high prices, and the regular (ethnic, e.g. Iranian) user who would be able to obtain larger quantities at much reduced prices from within the ethnic community.

Opium price reports since 1998 range from £2 to £100 per gram (mean price £19.26), and only seven ounce price reports from £15 to £120, a mean price of £71.12 per ounce (excluding two "free" reports).

Combined Results of IDMU Surveys 1994-2002 - Matthew J Atha & Simon T Davis

References

[1] Parker H, Newcombe RD & Bakx K (1987) Wirral"s Heroin Future - a second survey of the prevalence and characteristics of problem drug use in the Wirral 1985-6. Wirral Drug Abuse Committee/University of Liverpool

[2] Caplin S & Woodward S. (1986) Drugwatch - Just Say No! London: Corgi

[3] ` ISDD (1995) Drug Misuse in Britain 1994. London: ISDD Publications

[4] Gossop M, Griffiths P, & Strang J (1988) Chasing the Dragon: characteristics of heroin chasers. British Journal of Addiction 83 pp1159-1162

[5] Gossop M, Griffiths P, Powis B. & Strang J (1992) Severity of dependence and route of administration of heroin, cocaine and amphetamines British Journal of Addiction 87 pp1527-1536

[6] Parry A (1992). Taking heroin maintenance seriously: the politics of tolerance. The Lancet 339 (8-2-92) pp350-351

[7] King LA, Clarke K & Orpet AJ [1993] The Drug Content of Powders and Other Illicit Preparations. Drugs Intelligence Laboratory, Forensic Science Service, Aldermaston. Technical Note No. 780

[8] Stewart T (1996) The Heroin Users (2nd Ed). London: Harper Collins

[9] Higgins ST, Stitzer ML, McCaul ME, Bigelow GE, Liebson IA [1985] Pupillary response to methadone challenge in heroin users. Clin Pharmacol Ther 37(4):460-3

[10] Leeds Crown Court T 2001 7600

[11] Valenciano M, Emmanuelli J, Lert F. [2001] Unsafe injecting practices among attendees of syringe exchange programmes in France. Addiction 96(4):597-606

[12] Perneger TV, Mino A, Giner F, Broers B. [2000] Patterns of opiate use in a heroin maintenance programme. Psychopharmacology (Berl) 152(1):7-13

[13] Alvarez Mazariegos JA, Gonzalez Ferro A, Bobillo de la Pena MC, Garcia Mata A, del Alamo Alonso A, Pascua Garcia R.[1996] [Ambulatory opiate detoxification in primary care] [Article in Spanish] Aten Primaria 18(10):539-45

[14] Mendis N.[1985] Heroin addiction among young people: a new development in Sri Lanka. Bull Narc 1985 Apr-Sep;37(2-3):25-9

[15] Adityanjee DM, Saxena S, Lal S. [1985] Changing trends in heroin abuse in India: an assessment based on treatment records.Bull Narc 37(2-3):19-24

[16] Howe RC, Hegge FW, Phillips JL. [1980] Acute heroin abstinence in man: II. Alterations in rapid eye movement (REM) sleep. Drug Alcohol Depend 6(3):149-61

[17] Atha, & Blanchard (1997) op cit.

[18] Moore D. SaundersB & Hawks D. [1993] Recreational Drug Use, with particular reference to Amphetamines, Ecstasy and LSD, amongst a social network of young people in Perth, Western Ausrtalia. Curtin University of Technology. Bentley, Western Australia.

[ [19] Clarke K. Drugs Intelligence Laboratory, Aldermaston. personal communication 7-4-95.

[20] King LA, Clarke K & Orpet AJ [1993] op cit.

[21] King LA, Clarke K & Orpet AJ [1993] The Drug Content of Powders and Other Illicit Preparations. Drugs Intelligence Laboratory, Forensic Science Service, Aldermaston. Technical Note No. 780

[22] Corkey JM (2000) Drug Seizure and Offender Statistics, United Kingdom 1998. London: Home Office Statistical Bulletin issue 3/00.

[23] Home Office Statistical Bulleting 25/96 (28-11-96) Statistics of drugs seizures and offenders dealth with, UK 1995. London: HMSO - Table 2.6

[24] Humberside Police [1996] Humberside drug prices - January 1996. Disclosed during proceedings at Grimsby Crown Court, 25-1-96

[25] Hansard 1-4-98 - Commons Written Answers col 537 (George Howarth - Home Office)

[26] Atha MJ Blanchard S & Davis S (2001?) Regular Users IV - In Preparation

[27] Atha, Blanchard & Davis (2001?) - Regular Users IV - In preparation

[28] Mothner I & Weitz A [1984] How to Get Off Drugs. Penguin Health, 102-3

[29] British National Formulary No 35 (March 1998) pp200-205

[30] Fountain J, Stang J, Gossop M, Farnell M & Griffiths P (2000) Diversion of prescribed drugs by drug users in treatment: analysis of the UK market and new data from London. Addiction 95(3) pp393-406.

[31] Booth M (1997) Opium, a History. Pocket Books, p28 - 40-70 grains, one part opium to 10 parts other ingredients, = 236-414mg

[32] Von Bibra E (1855) Plant Intoxicants Trans 1995: Rochester Vt. Healing Arts Press, pp124-126.

[33] US Department of State (1996) Map of Major Opium & Coca Producing Countries. Bureau of international law enforcement. US Government Printing Office

[34] Hogshire J (1994) Opium for the Masses. Port Townsend Wa. Lumpanics Un-Ltd.

[35] Corkery JM (2001) Drug Seizure and Offender Statistics, United Kingdom, 1999. Home Office Statistical Bulletin Issue 5/01. London: Home Office

[36] Atha MJ (1984) op cit

[37] The Guardian 23-11-99

[38] HMCE National Investigation Service. UK Drug Prices (as at September 1996)

[39] NCIS - UK Drug Prices (as at December 1997)

[40] Greater Manchester Police - drug unit Appendix A - Street prices (Sept 96)

[41] Atha MJ (1984) op cit

Independent Drug Monitoring Unit

UK Opiate Usage

Consumption, Attitudes and Prices

Heroin

Consumption - The Literature

Case Histories

IDMU Surveys

Heroin Purities:

UK Heroin prices

Methadone

IDMU surveys

Prescription

Street Prices

Other Opiates

IDMU Surveys

Opiate Tablet Prices

Opium

Prevalence

IDMU Surveys

Opium Prices

Conclusions

Heroin

Methadone

Other Opiates

Opium

Combined Results of IDMU Surveys 1994-2002 - Matthew J Atha & Simon T Davis

References