From the clinic to the street: the changing role of benzodiazepines in the Scottish overdose epidemic.

Drug-related deaths in Scotland increased for seven years in a row between 2014 and 2020 consolidating Scotland's place at the top of the United Kingdom and European drug-related mortality charts. One of the defining features of this recent and rapid rise has been the role of benzodiazepines which are now involved in two-thirds of all cases. Policy decisions over four decades have contributed to the supply and demand drivers of this unique element of the Scottish overdose crisis. An illicit market once populated by diverted prescription medications is now dominated by a toxic supply of NPS-type benzodiazepines or so-called 'street benzos' which have increased the risk environment for people who use drugs. In response, Scotland needs to urgently expand its harm reduction infrastructure and implement safer supply, drug testing and drug consumption rooms. Such a response should be made in parallel to addressing the socioeconomic inequalities which are fuelling an epidemic of global significance.

Continued drug use and other cofactors for progression to AIDS among injecting drug users.

OBJECTIVE: To evaluate the effects of continued drug use and other cofactors on progression to AIDS among HIV-infected injecting drug users. DESIGN: A prospective study. SETTING: The Muirhouse Medical Group in Edinburgh, Scotland, UK. SUBJECTS: A total of 156 HIV-infected injecting drug users. MAIN OUTCOME MEASURES: Progression to AIDS and low absolute CD4 counts. RESULTS: Of this group, 48% will have progressed to AIDS 10 years after seroconversion. Age and low absolute T4 counts had a significant effect on progression to AIDS, with older patients progressing more rapidly. Sex had no significant effects on progression. Absolute CD4+ counts and the CD4:CD8 ratio were significant predictors of progression among the group. Concurrent heroin injecting increased the risk of progression to AIDS. No significant effects were observed for use of other drugs. CONCLUSIONS: Our findings suggest that continued drug use may have an accelerating effect on progression to AIDS. Age also had an accelerating effect on progression, but sex had no significant effects. In general, the study group did not appear to progress at a different rate from other similar groups of HIV-infected individuals, despite the fact that this was a relatively young cohort. These data were based on accurate estimates of seroconversion dates.

Beta 2-microglobulin levels in drug users: the influence of risk behaviour.

beta 2-microglobulin (beta 2M) levels were measured in 217 Edinburgh drug users to assess their usefulness as a marker for HIV-related disease. Eighty HIV-seronegative drug injectors had significantly higher levels than 100 HIV-seronegative blood-donor controls. Amongst 137 asymptomatic HIV-seropositive drug users, those who were defined as continued drug users had significantly higher beta 2M levels and percentages of CD3+ T lymphocytes with DR Class II expression than non-injecting drug users. beta 2M levels correlated with the percentage of activated DR+ CD3+ T lymphocytes. These findings indicate that changes in beta 2M levels may reflect differences in drug-injecting behaviour and are not influenced solely by HIV status or progression. These changes in beta 2M probably represent differing degrees of immunostimulation resulting from the antigenic challenges afforded by continued or frequent drug injection. It is important to establish normal ranges for beta 2M from HIV-seronegative controls who are matched with respect to risk group and behaviour. All these factors should be taken into account if beta 2M is to be used as a marker of HIV progression.

Has the rate of progression to AIDS changed in recent years?

OBJECTIVES: To investigate whether the rate of progression to AIDS has changed over time by testing an effect of the year of seroconversion on AIDS onset (Centers for Disease Control and Prevention 1987 revised classification), next to an effect of the calendar period of follow-up. DESIGN: French multicentre prospective study of 385 homosexual and heterosexual subjects and 231 subjects from a multicentre study of European injecting drug users (IDU), all with a documented date of HIV-1 seroconversion. METHOD: The effect of the year of seroconversion was compared by the log-rank test. Crude and adjusted relative hazard (ARH) were quantified using the Cox model. Calendar period of follow-up was studied separately for sexual exposure group and IDU and treated as a time-dependent variable in a Cox model. RESULTS: In the 616 study subjects the year of seroconversion was not significantly related to AIDS occurrence (n = 108); the ARH was 0.88 [95% confidence interval (CI), 0.56-1.38] for those who seroconverted in 1988-1989, and 1.17 (95% CI, 0.61-2.25) for those who seroconverted after 1989, compared with those who seroconverted before 1988. In the sexual exposure group, a clear trend towards less rapid progression to AIDS was observed in subjects followed in 1991-1992 (ARH, 0.49; 95% CI, 0.24-0.99) and after 1992 (ARH, 0.54; 95% CI; 0.24-1.21), compared with those followed before 1991. This favorable trend was not observed in IDU despite a significant decrease over time of Pneumocystis carinii pneumonia as AIDS-defining illness. Conversely to sexual exposure groups, the frequency of antiretroviral treatment (mainly zidovudine) prescription was still low during the most recent calendar periods in IDU when the CD4 count threshold of 200 x 10(6)/l was reached. CONCLUSIONS: No evidence was found of a change in the rate of progression to AIDS in subjects who seroconverted in recent years. Furthermore, conversely to sexual exposure groups, the lack of favorable trends in IDU users followed in recent years suggest that health-care systems are not always adapted to their lifestyles.

Pre-AIDS mortality from natural causes associated with HIV disease progression: evidence from the European Seroconverter Study among injecting drug users.

OBJECTIVES: To study differences in pre-AIDS mortality between European cohorts of injecting drug users (IDU) and to evaluate whether pre-AIDS mortality increased with time since HIV seroconversion and decreasing CD4 count. METHODS: The study population consisted of 664 IDU with documented intervals of HIV seroconversion from eight cohort studies. Differences in pre-AIDS mortality were studied between European sites; an evaluation of whether pre-AIDS mortality increased with time since HIV seroconversion and decreasing CD4 count was carried out using Poisson regression. RESULTS: One hundred and seven IDU died, of whom 57 did not have AIDS. Pre-AIDS causes of death were overdose/suicide (49%), natural causes such as bacterial infections/cirrhosis (40%), and unintentional injuries/unknown (11%). Considering pre-AIDS death and AIDS as competing risks, 14.7% were expected to have died without AIDS and 17.3% to have developed AIDS at 7 years from seroconversion. No statistically significant differences in pre-AIDS mortality were found between European regions, men and women, age categories and calendar time periods. Overall pre-AIDS mortality did not increase with time since seroconversion, but did increase with decreasing CD4 count. Evaluating cause-specific mortality, only pre-AIDS mortality from natural causes appeared to be associated with time since seroconversion as well as immunosuppression. For natural causes, the death rate per 100 person-years was 0.13 the first 2 years after seroconversion, 0.73 in years 2-4 [risk relative (RR) to years 0-2, 5.6], 1.83 in years 4-6 (RR, 14.0) and 1.54 for > or = 6 years (RR, 11.7). This rate was 0 for a CD4 cell count > or = 500 x 10(6)/l, 1.06 for 200-500 x 10(6)/l and 4.06 for < 200 x 10(6)/l (RR versus > or = 200 x 10(6)/l, 7.0). In multivariate analysis, both CD4 count and time since seroconversion appeared to be independently associated with death from natural causes; CD4 count appeared to be the strongest predictor (adjusted RR, 5.9). CONCLUSIONS: A high pre-AIDS mortality rate was observed among IDU. No significant differences were observed across European sites. Pre-AIDS mortality from natural causes but not from overdose and suicide was associated with HIV disease progression.

Do gender differences in CD4 cell counts matter?

OBJECTIVE: To examine the effect of gender on disease progression and whether gender differences in CD4 lymphocyte counts persisted for the entire course from HIV seroconversion until (death from) AIDS. METHODS: CD4 lymphocyte counts were modelled in 221 female and 443 male seroconverters following seroconversion, backwards from AIDS and backwards from death using regression analysis for repeated measurements. RESULTS: In the period before use of highly active antiretroviral therapy (HAART), progression to AIDS and to death were marginally slower in women than in men as assessed by proportional hazards analysis. Women seroconverted for HIV, developed AIDS and died at higher CD4 cell counts than men (women: 815, 146 and 44 x 10(6) cells/l, respectively; men: 727, 49 and 22 x 10(6) cells/l, respectively), although differences were only statistically significant at AIDS onset. Declines in CD4 lymphocyte counts were not significantly affected by gender and absolute differences between men and women were stable, with exception for the trajectory close to AIDS when the decline became steeper for men than women. CONCLUSION: These gender differences in CD4 lymphocyte counts suggest a delay of initiation of therapy in women compared with men (our model predicted that women reach the threshold of starting HAART at about 12 months later than men). If this delay unfavourably influences progression, treatment guidelines should be revised so that women can benefit equally from HAART.

Geographical variation in disease progression in HIV-1 seroconverted injecting drug users in Europe?

BACKGROUND: Human immunodeficiency virus (HIV) disease progression might vary by geographical region due to differences in the spectrum of HIV-related illnesses and (access to) health care. Therefore, the effect of geographical region, next to the effect of other potential cofactors, on disease progression in 664 injecting drug users (IDU) with documented HIV seroconversion from eight cohorts in Europe was studied. METHODS: Kaplan-Meier methods and Cox proportional hazards analysis were performed to assess the effect of geographical region, other sociodemographics, drug use and repeated HIV exposure on progression from HIV seroconversion to immunosuppression, AIDS and death with AIDS. We considered the confounding effect of study-design related factors (e.g. setting of follow-up), and accounted for pre-AIDS death from natural causes by imputing when each endpoint would have occurred, had they not died without AIDS. RESULTS: Estimates of progression to AIDS and death with AIDS were substantially faster after taking pre-AIDS mortality into account. Median incubation time from seroconversion to the first CD4 count < 200 cells/microliter was 7.7 years (95% CI: 7.1-8.3) and to AIDS 10.4 years (95% CI: 9.8-infinity). The 10-year survival was 70.3% (95% CI: 62.8-76.6). The relative hazards (RH) of AIDS for IDU from central and southern Europe compared with IDU from northern Europe was 1.9 (95% CI: 1.2-3.0) and 1.2 (95% CI: 0.6-2.3), respectively, before, and 1.5 (95% CI: 0.7-3.2) and 1.1 (95% CI: 0.6-2.3) after taking differences in study-design related factors into account. Accounting for these factors, the RH of death with AIDS was 0.9 (95% CI: 0.3-2.5) for central and 1.2 (95% CI: 0.4-3.4) for southern Europe compared with northern Europe. For the first CD4 count < 200 cells/microliter these figures were 0.8 (95% CI: 0.5-1.4) and 0.8 (95% CI: 0.5-1.4). Age at seroconversion was the strongest predictor of disease progression. No statistically significant differences in disease progression were found by gender, foreign nationality, drug use and potential repeated HIV exposure. CONCLUSIONS: We found no evidence for regional variability in HIV disease progression among European IDU. Future studies evaluating geographical differences should consider the confounding effect of study-design related factors and differential non-AIDS mortality. As age is an important determinant of disease progression, it should be considered in recommending treatment.

Schizophrenia with karyotype mosaic 47,XXY/48,XXY + 8.

A case of severe schizophrenia is described in a patient with chromosomal mosaicism of Klinefelter's syndrome (XXY) and trisomy 8. The literature of both syndromes is reviewed and the aetiological implications discussed.

Suburethral diverticula treated by marsupialization.

This study reports the results of therapy for 8 patients in whom the diagnosis of suburethral diverticulum had been missed for many years. The treatment of these patients utilized a new surgical technic of marsupialization which is described in detail. In all patients, the time of operation was short, blood loss minimal, and the surgery resulted in relief of symptoms. No complications were noted with marsupialization as compared with the 17% overall complication rate of diverticulectomy, the present standard therapy. In addition, a literature survey of this disorder is presented as well as a program for adequate diagnostic evaluation of a patient with a urinary tract disorder.

Association of HLA types A1-B8-DR3 and B27 with rapid and slow progression of HIV disease.

We examined how HLA types A1-B8-DR3 and B27 were related to progression of clinical disease and rate of loss of CD4 lymphocytes in the Edinburgh City Hospital cohort of HIV-positive patients, mainly injection drug users. Patients (n = 692) were prospectively followed from 1985 through March 1994. Accurately estimated seroconversion times were determined retrospectively for a subgroup of 313 (45%). Of 262 patients (39%) who were fully or partially HLA typed, 155 (50%) had known seroconversions. Of 34 patients typed positive for A1-B8-DR3, 29 progressed to CDC stage IV, 22 to AIDS and 20 died. Twelve patients were typed positive for B27; six of these progressed to CDC stage IV, one to AIDS and none died. In a proportional hazards analysis of the 313 patients with known seroconversions, A1-B8-DR3 was significantly associated with covariate-adjusted relative risks of 3.7 (95% CI 1.9-7.2), 3.1 (1.6-6.0) and 1.9 (1.1-3.2) for progression from seroconversion to death, AIDS and CDC stage IV, respectively. Events for B27 were too rare to include B27 in analyses to death and AIDS, but B27 was significantly associated with slower progression to CDC stage IV (0.3, CI 0.1-0.9). Random effects growth curve models were used to estimate individual rates of loss of square root CD4 count and loss of CD4 percentage, for 603 and 617 patients, respectively. A1-B8-DR3 was associated with rapid loss of both markers (p = 0.02 and p = 0.01, respectively); B27 was associated with slow loss of both markers (p = 0.04 and p < 0.005).

Initial and current drug use: how are they related?

The present study examines how initial and current patterns of drug use are related among a group of drug users in Edinburgh. The study categorised individuals according to the year in which they first used illicit drugs. 1984 has been shown to be the year when patterns of drug use in this group began to change after high levels of heroin use in the late 1970s and early 1980s. Thus 1984 was used as the intercept point to create two groups: the epidemic group, comprising individuals who began using illicit drugs before 1984, and, the post epidemic group, who began using during or after 1984. Data from individuals were gathered from interviews and medical records. Statistical analysis revealed interesting differences between the groups, for example, the groups did not differ significantly in their use of methadone but the epidemic group used more methadone obtained on prescription. The post epidemic group was found to inject more often, but, did not share injecting equipment more than the epidemic drug users. A greater number of the epidemic group began using drugs by injecting and a greater number of the post epidemic group began by taking drugs orally. The issues raised by the results are discussed, and, it is suggested that the characteristics of the drug using community within which an individual begins using drugs may exert influence on patterns of drug use in later years.

The epidemiology of HIV infection in Edinburgh related to the injecting of drugs: an historical perspective and new insight regarding the past incidence of HIV infection derived from retrospective HIV antibody testing of stored samples of serum.

The pattern of sudden explosive outbreaks of HIV infection among drug users has been seen in several countries but is as yet incompletely understood. The epidemic of injecting drugs in Edinburgh was associated with at least four overlapping epidemics of blood-borne viruses (hepatitis B, C, D and HIV). Only hepatitis B was initially recognized, being followed by HIV and latterly hepatitis C. Retrospective HIV testing of stored samples of serum from clinically diagnosed patients with HIV has allowed the HIV epidemic to be delineated and more accurate seroconversion dates identified for most of the patients. There is evidence to suggest that the explosive drug-related Edinburgh HIV epidemic may have been self-terminating and that the epidemic in male drug users preceded that in female drug users by around 3 months. We suggest that the self-terminating nature of this epidemic may have been related to changes in drug injecting behaviour or to varying infectivity of the virus. This latter possibility should be explored in future studies of HIV transmission.

Absence of hepatitis C virus transmission but frequent transmission of HIV-1 from sexual contact with doubly-infected individuals.

Hepatitis C virus (HCV) is transmitted through infected blood and blood products, but evidence of other routes of transmission is less clearly understood. In a study designed to examine human immunodeficiency virus (HIV) transmission, the prevalence of HCV has also been measured. Sixty-one couples were analysed, 30 in which partners were at risk through sexual contact alone, of whom 12 (40%) became infected with HIV and none with HCV. Thirty-one partners were exposed sexually and additionally through intravenous drug use. Of these, 16 (52%) became infected with HIV and 25 (80%) contracted HCV infection. These findings support the evidence of others that HCV is only rarely transmitted by sexual intercourse in heterosexual relationships and that HIV is not a co-factor for HCV transmission.

Laryngeal problems following infant esophageal surgery.

This paper focuses on vocal cord paralysis in children after operation for tracheoesophageal fistula and/or esophageal atresia. We reviewed the charts of 65 children who were operated upon for congenital esophageal atresia and/or tracheoesophageal fistula during a period from 1964 to 1974. Ten of these children manifested laryngeal symptoms. Five had laryngeal paralysis. Two were untreated. One was treated with cordectomy and stent. Two were treated successfully with the Thornell arytenoidectomy, one of these being done without a tracheotomy in place. Mention is made of a third case of bilateral vocal cord paralysis due to hydrocephalus treated successfully by the Thornell procedure. Follow-up laryngoscopy was done on 21 children without laryngeal symptoms whiich revealed two previously unsuspected vocal cord paralyses and one vocal cord paresis which cleared.

Cannabis use in the community.

BACKGROUND: The illegal use of cannabis has been increasing in many Western countries for the past two decades. Recently, some interest has been shown in modifying legislation and control. The need for general practitioners to be aware of the short- and long-term consequences of cannabis use is increasing, and more information is required about its effects on behaviour, psychological states and the respiratory and cardiovascular systems. The use of general practice populations to study the prevalence of cannabis use and its damaging effects is less represented in the literature than it should be, considering the extent of cannabis consumption. AIM: A study was carried out in 1995 to determine the prevalence of cannabis use in a general practice population and any associated health problems. As a pilot study, samples of cannabis were obtained for forensic analysis. METHOD AND PATIENTS: Two questionnaires were used. One very short enquiry about the use, if any, of the drug, and a longer one about the effects of its use. Data concerning medical effects were included from patients' case notes. Samples of cannabis were obtained for forensic examination. RESULTS: A very high proportion (61%) of patients surveyed indicated some cannabis use (past or present). Thirty-seven per cent had used it in the previous 12 months. Users could be broadly divided into transitory experimenters, regular users and heavy users. Medical problems included those attributed to associated tobacco smoking, other illegal drug use and psychological problems. Benefits perceived by patients recording use were many. Polydrug use and legislation issues were difficult to separate from the effects of cannabis itself. Chest infections, anxiety and depression, and drug dependence were common diagnoses, and 13 of the 32 females in the study group had evidence of cervical smear abnormalities. CONCLUSIONS: Few serious damaging effects from cannabis use itself were identified, although chest infections and anxiety problems were common. Tobacco damage, associated drug use and criminal or legal issues dominated and obscured the important perceived benefits and the scientific understanding of the effects and side effects of the drug. More research into several identified areas is required.

Problems of drug abuse, HIV and AIDS: the burden of care in one general practice.

Responsibility for many of the problems of intravenous drug abuse and human immunodeficiency virus (HIV) infection lies with community care agencies, such as general practitioners, community psychiatric and district nurses and drug agencies. It is in general practice that this burden is most clearly observed, given that general practitioners are in charge of the day-to-day care of patients. In an attempt to quantify this workload in an inner city practice with 11,200 patients, data were gathered from several sources relating to drug use and HIV infection. The study identified 432 patients who had consulted with problems of drug abuse and/or HIV infection over the period 1981-90. Among this group of patients 161 (37%) were HIV antibody positive. Among 191 drug abusers who were still registered with the practice in 1990 dihydrocodeine was the most commonly prescribed substitute treatment (130 patients) and only nine patients were prescribed methadone. Forty seven per cent of drug users continued to inject drugs occasionally. However, analysis of urine samples revealed that there was a shift away from injecting mainly heroin to multiple drug use, including benzodiazepines, usually originating from prescribed sources. Drug abusers who were HIV positive consulted their general practitioner significantly more often over one year than those who were not (mean 24.9 versus 15.8 consultations, P < 0.01). However, there was no significant difference between these two groups in terms of days spent in hospital. A total of 61 patients were referred to a community psychiatric nurse over an eight month period.(ABSTRACT TRUNCATED AT 250 WORDS)

HIV testing and prevalence in pregnancy in Edinburgh.

The objective was to study the changes in pregnancy HIV prevalence with time. Data were collected from multiple sources to provide a comprehensive record of all HIV seropositive pregnant women identified in the Edinburgh area (Scotland) until December 1992. There were 177 pregnancies in 108 HIV seropositive identified women. Risk factors were injection drug use (79% of pregnancies) and a known HIV seropositive injection drug-using partner (16%). Prevalence has decreased for Edinburgh City women from 0.5% of all pregnancies in 1986 to 0.1% in 1992; It was higher for induced abortion (0.6%) than for delivery (0.2%). HIV testing in pregnancy has declined. Comparison with unlinked anonymized testing showed that in 1990-1991, 20/22 seropositive women were known. In 1992, only 3 of 10 seropositive pregnancies were identified. The cohort initially infected by exposure to a 'drug related' risk factor between 1983 and 1985 may have increasingly finished childbearing, deliberately decided against pregnancy because of HIV status, and declined because of death, illness and emigration from the area, There may not have been major early tertiary heterosexual spread; however, data from 1992 suggest that this could now be impacting on pregnancy prevalence. Local testing policies have not adapted to this possible change.

Characteristics of patients less than 45 years of age compared with older patients undergoing coronary artery bypass grafting.

BACKGROUND: Coronary artery disease (CAD) was not recognized as common among young patients until the study by Yater in 1948. Subsequent studies further elucidated the nature of the disease, which had become more apparent in the younger groups. HYPOTHESIS: The study was undertaken to determine the prevalence of risk factors and severity of coronary disease among young patients aged < or = 45 years undergoing coronary artery bypass grafting (CABG) compared with older patients. METHODS: In all, 112 young patients aged < or = 45 years (Group 1) and 798 older patients aged > 45 years (Group 2) were analyzed for trends to hypertension, smoking, diabetes, family history of heart disease, hypercholesterolemia, obesity, and history of previous myocardial infarction (MI). The severity of disease was examined in terms of number of diseased vessels, vessel size, number of grafts performed, performance of endarterectomies, and left ventricular function. RESULTS: Group 1 had a higher incidence of positive family history (68.5 vs. 51.2%, p < 0.05), and lower incidences of hypertension (62.7 vs. 81.5%, p < 0.05), obesity (42.9 vs. 83.9%, p < 0.05), and history of previous MI (54.5 vs. 94.6%, p < 0.05). Group 2 had a higher incidence of left main disease (22.6 vs. 11.4%, p < 0.05). The distribution of the affected vessels of the young patients was most commonly the left anterior descending (90.4%) followed by the right coronary (79.8%) and circumflex arteries (69.2%). Group 2 had more grafts per patient (3.82 vs. 3.37, p < 0.05). The size of the diseased vessels measured intraoperatively was similar (1.56 vs. 1.58 mm, p = NS) in both groups. Endarterectomy was performed almost three times more often in Group 1 patients (8.2 vs. 3.0%, p < 0.05). Operative mortality was less in Group 1 mean (1.8 vs. 6.3%, p < 0.05). Group 2 had a greater mean left ventricular ejection fraction (53.8 vs. 49.7%, p < 0.05). CONCLUSION: Compared with the older population, patients < or = 45 years of age who underwent CABG had (1) a higher incidence of positive family history of CAD, (2) a higher likelihood of requiring an endarterectomy, and (3) lower operative mortality rate despite a slightly poorer ventricular function.

The analysis of methadone in nail clippings from patients in a methadone-maintenance program.

This study offers an analytical scheme for methadone in fingernail clippings. Nail specimens (0.18-16.33 mg) were collected from 30 consenting adults participating in a methadone-maintenance program along with questionnaires regarding their drug-use histories. The nail clippings were stored in plastic bags and transferred to the laboratory for analysis. They were decontaminated by sonication for 15-min intervals successively in 0.1% sodium dodecyl sulfate, water (three times), and methanol (three times). The methanolic washes were collected and screened for methadone by enzyme immunoassay (EIA). Three washes were found sufficient to provide EIA negative results. The decontaminated nail clippings were hydrolyzed in 1M NaOH. Aliquots of the hydrolysates were screened for methadone by EIA and confirmed by gas chromatography-mass spectrometry (GC-MS). The mean methadone concentrations in fingernail clippings determined by EIA and GC-MS were 32.8 and 26.9 ng/mg, respectively. Hydrolysates of the equivalent of 10 mg of blank nail clippings were spiked with known concentrations of methadone and analyzed by the developed procedures in order to determine extraction recoveries and limits of detection of the two techniques. Based on our results, fingernails appear to be a potentially useful biological specimen for the analysis of methadone and the monitoring of patient compliance to methadone-maintenance programs.

Nail analysis for drugs of abuse: extraction and determination of cannabis in fingernails by RIA and GC-MS.

Fingernail clippings were evaluated as analytical specimens for the detection and quantitation of cannabinoids. Specimens were obtained from consenting adults attending a drug clinic, along with information concerning the drugs which they had used over the previous six months. Methods for the surface decontamination and extraction of the specimens were evaluated. Detergent, water, and methanol washes followed by alkaline hydrolysis and liquid-liquid extraction were selected for use in the study. Extracts were analyzed by radioimmunoassay (RIA) and gas chromatography-mass spectrometry (GC-MS) to detect and quantitate cannabinoids present in fingernail clippings. Positive RIA results were obtained from specimens from six known cannabis users. The mean cannabinoid concentration in fingernail clippings determined by RIA was 1.03 ng/mg. Using GC-MS, the mean delta9-tetrahydrocannabinol concentration in fingernail clippings from a further 14 known cannabis users was 1.44 ng/mg. Using GC-MS, the average 11-nor-delta9-tetrahydrocannabinol-9-carboxylic acid concentration in fingernail clippings from three known cannabis users extracted in acidic pH was 19.85 ng/mg. Based on these results, fingernails are potentially useful biological specimens for the detection of past cannabis use in cases of medicolegal interest.