A twin study of personality and illicit drug use and abuse/dependence.

Although personality measures such as neuroticism (N), extraversion (E) and novelty-seeking (NS) are associated with the use and abuse/dependence of illicit drugs, little is known about the degree to which these associations are due to genetic or environmental factors. The goal of this analysis was to estimate the extent of genetic and environmental overlap between three dimensions of personality (N, E and NS) and illicit psychoactive substance use and abuse/dependence. Using data from adult male and female twins from the Mid-Atlantic Twin Registry, we used the structural equation modeling package Mx to perform bivariate Cholesky decompositions for personality measures of N, E and NS, individually with cannabis, cocaine, sedatives, stimulants and hallucinogens. This was done separately for use and for a polychotomous diagnosis of abuse and/or dependence. Sex differences were tested. The phenotypic relationship between personality and use and abuse/dependence of illicit drugs were moderate and most of the covariance was explained by genetic factors. Sexes could be equated for N and E but not for NS. For NS, use and abuse/dependence of illicit drugs showed greater phenotypic and genetic overlap in males than females. Of the personality measures, NS and illicit drug use and abuse/dependence were most closely related. NS was most closely related to cannabis use while N showed significant genetic overlap with sedative use. NS in males appears to be a good indicator of risk for cannabis use. This result may be useful for candidate gene studies.     

Diagnostic Yield of Universal Urine Toxicology Screening in an Unselected Cohort of Stroke Patients

Background

Illicit drug use increases the risk of cerebrovascular events by a variety of mechanisms. A recent report suggested that universal urine toxicology (UTox) screening of patients with stroke may be warranted. We aimed to evaluate the diagnostic yield of urine drug screening among unselected patients admitted with acute stroke or transient ischemic attack (TIA).

Methods

Using a single-center prospective study design, we evaluated consecutive patients with acute ischemic stroke, TIA, intracerebral hemorrhage (ICH), or subarachnoid hemorrhage (SAH) over one year. Urine samples were collected within 48 hours of admission and analyzed for common classes of abused drugs. Prevalence of positive UTox screening was determined. We evaluated whether baseline demographics and clinical factors were associated with UTox results.

Results

Of 483 eligible patients (acute ischemic stroke 66.4%; TIA 18.8%; ICH 7.7%; SAH 7.0%), 414 (85.7%) completed UTox screening. The mean (standard deviation) age was 65.1 (15.6) years, 52.7% were male, and 64.3% were Caucasian. Twenty-two (4.6%) patients had positive screening—cannabinoids were detected in 13 cases (3.1%), cocaine in 5 cases (1.2%), amphetamines in 1 case, and phencyclidine in 1 case. The highest yield (14.1%) was observed in patients < 60 years old with history of tobacco use while it was < 5% in the remaining subgroups (p<0.01).

Conclusions

Consistent with current guidelines, a selective approach to UTox screening should be pursued in acute stroke evaluation. The highest diagnostic yield is likely to be for cannabinoids and cocaine testing in younger patients with a history of concurrent tobacco use.     

Hair testing for drugs of abuse

Hair testing for drugs of abuse is a developing technology, which offers the possibility of longer detection times than is commonly obtained with urine analysis. It is the main method for evaluation of an individual's drugs of abuse history. In many countries hair analysis is routinely used to detect drug abuse in forensic cases, occupational and traffic medicine and clinical toxicology. Hair analysis in pregnant women, neonates and infants is a useful tool for the detection of drug exposure in utero. In Croatia hair testing for drugs of abuse is performed at the Institute for Medical Research and Occupational Health. Three-year experience in drugs of abuse analysis in hair is described. In 331 hair samples (270 from adolescents and 61 from adults) opiates and metabolites, cocaine, methadone, and amphetamines were analyzed by gas chromatography/mass spectrometry. Most prevalent drugs of abuse in adolescents were amphetamines, and in adults heroin. From the examples cited and samples analyzed it is evident that hair testing is emerging as a reliable biological marker for cumulative account of individual exposure to drugs of abuse.     

Hand Function is Altered in Individuals with a History of Illicit Stimulant Use

Use of illicit stimulant drugs such as methamphetamine, cocaine, and ecstasy are a significant worldwide problem. However, little is known about the effect of these drugs on movement. The aim of the current study was to investigate hand function in adults with a history of illicit stimulant use. We hypothesized that prior use of illicit stimulant drugs is associated with abnormal manipulation of objects. The study involved 22 subjects with a history of illicit stimulant use (aged 29±8 yrs; time since last use: 1.8±4.0 yrs) and two control groups comprising 27 non-drug users (aged 25±8 yrs) and 17 cannabis users with no history of stimulant use (aged 22±5 yrs). Each subject completed screening tests (neuropsychological assessment, medical history questionnaire, lifetime drug history questionnaire, and urine drug screen) prior to gripping and lifting a light-weight object with the dominant right hand. Horizontal grip force, vertical lift force, acceleration, and first dorsal interosseus electromyographic (EMG) activity were recorded during three trials. In trial one, peak grip force was significantly greater in the stimulant group (12.8±3.9 N) than in the control groups (non-drug: 10.3±4.6 N; cannabis: 9.4±2.9 N, P<0.022). However, peak grip force did not differ between groups in trials two and three. The results suggest that individuals with a history of stimulant use overestimate the grip force required to manipulate a novel object but, are able to adapt grip force in subsequent lifts. The results suggest that movement dysfunction may be an unrecognized consequence of illicit stimulant use.     

Reward-Related Attentional Bias and Adolescent Substance Use: A Prognostic Relationship?

Current cognitive-motivational addiction theories propose that prioritizing appetitive, reward-related information (attentional bias) plays a vital role in substance abuse behavior. Previous cross-sectional research has shown that adolescent substance use is related to reward-related attentional biases. The present study was designed to extend these findings by testing whether these reward biases have predictive value for adolescent substance use at three-year follow-up. Participants (N = 657, mean age = 16.2 yrs at baseline) were a sub-sample of Tracking Adolescents’ Individual Lives Survey (TRAILS), a large longitudinal community cohort study. We used a spatial orienting task as a behavioral index of appetitive-related attentional processes at baseline and a substance use questionnaire at both baseline and three years follow-up. Bivariate correlational analyses showed that enhanced attentional engagement with cues that predicted potential reward and nonpunishment was positively associated with substance use (alcohol, tobacco, and cannabis) three years later. However, reward bias was not predictive of changes in substance use. A post-hoc analysis in a selection of adolescents who started using illicit drugs (other than cannabis) in the follow-up period demonstrated that stronger baseline attentional engagement toward cues of nonpunishment was related to a higher level of illicit drug use three years later. The finding that reward bias was not predictive for the increase in substance use in adolescents who already started using substances at baseline, but did show prognostic value in adolescents who initiated drug use in between baseline and follow-up suggests that appetitive bias might be especially important in the initiation stages of adolescent substance use.     

Substance use in remand prisoners: a consecutive case study.

OBJECTIVES: To determine the prevalence of drug and alcohol use among newly remanded prisoners, assess the effectiveness of prison reception screening, and examine the clinical management of substance misusers among remand prisoners. DESIGN: A consecutive case study of remand prisoners screened at reception for substance misuse and treatment needs and comparison of findings with those of prison reception screening and treatment provision. SETTING: A large adult male remand prison (Durham). SUBJECTS: 548 men aged 21 and over awaiting trial. MAIN OUTCOME MEASURES: Prevalence of substance misuse; treatment needs of substance misusers; effectiveness of prison reception screening for substance misuse; provision of detoxification programmes. RESULTS: Before remand 312 (57%) men were using illicit drugs and 181 (33%) met DSM-IV drug misuse or dependence criteria; 177 (32%) men met misuse or dependence criteria for alcohol. 391 (71%) men were judged to require help directed at their drug or alcohol use and 197 (36%) were judged to require a detoxification programme. The prison reception screen identified recent illicit drug use in 131 (24%) of 536 men and problem drinking in 103 (19%). Drug use was more likely to be identified by prison screening if an inmate was using multiple substances, using opiates, or had a diagnosis of abuse or dependence. 47 (9%) of 536 inmates were prescribed treatment to ease the symptoms of substance withdrawal. CONCLUSIONS: The prevalence of substance misuse in newly remanded prisoners is high. Prison reception health screening consistently underestimated drug and alcohol use. In many cases in which substance use is identified the quantities and numbers of different substances being used are underestimated. Initial management of inmates identified by prison screening as having problems with dependence producing substances is poor. Few receive a detoxification programme, so that many are left with the option of continuing to use drugs in prison or facing untreated withdrawal.     

Importance of Thinking Locally for Mental Health: Data from Cross-Sectional Surveys Representing South East London and England

Background

Reliance on national figures may be underestimating the extent of mental ill health in urban communities. This study demonstrates the necessity for local information on common mental disorder (CMD) and substance use by comparing data from the South East London Community Health (SELCoH) study with those from a national study, the 2007 English Adult Psychiatric Morbidity Study (APMS).

Methodology/Principal Findings

Data were used from two cross-sectional surveys, 1698 men and women residing in south London and 7403 men and women in England. The main outcome, CMD, was indicated by a score of 12 or above on the Revised Clinical Interview Schedule. Secondary outcomes included hazardous alcohol use and illicit drug use. SELCoH sample prevalence estimates of CMD were nearly twice that of the APMS England sample estimates. There was a four-fold greater proportion of depressive episode in the SELCoH sample than the APMS sample. The prevalence of hazardous alcohol use was higher in the national sample. Illicit drug use in the past year was higher in the SELCoH sample, with cannabis and cocaine the illicit drugs reported most frequently in both samples. In comparisons of the SELCoH sample with the APMS England sample and the APMS sample from the Greater London area in combined datasets, these differences remained after adjusting for socio-demographic and socioeconomic indicators for all outcomes.

Conclusions/Significance

Local information for estimating the prevalence of CMD and substance use is essential for surveillance and service planning. There were similarities in the demographic and socioeconomic factors related to CMD and substance use across samples.     

Illicit Stimulant Use Is Associated with Abnormal Substantia Nigra Morphology in Humans

Use of illicit stimulants such as methamphetamine, cocaine, and ecstasy is an increasing health problem. Chronic use can cause neurotoxicity in animals and humans but the long-term consequences are not well understood. The aim of the current study was to investigate the long-term effect of stimulant use on the morphology of the human substantia nigra. We hypothesised that history of illicit stimulant use is associated with an abnormally bright and enlarged substantia nigra (termed ‘hyperechogenicity’) when viewed with transcranial sonography. Substantia nigra morphology was assessed in abstinent stimulant users (n = 36; 31±9 yrs) and in two groups of control subjects: non-drug users (n = 29; 24±5 yrs) and cannabis users (n = 12; 25±7 yrs). Substantia nigra morphology was viewed with transcranial sonography and the area of echogenicity at the anatomical site of the substantia nigra was measured at its greatest extent. The area of substantia nigra echogenicity was significantly larger in the stimulant group (0.273±0.078 cm²) than in the control (0.201±0.054 cm²; P<0.001) and cannabis (0.202±0.045 cm²; P<0.007) groups. 53% of stimulant users exhibited echogenicity that exceeded the 90^th percentile for the control group. The results of the current study suggest that individuals with a history of illicit stimulant use exhibit abnormal substantia nigra morphology. Substantia nigra hyperechogenicity is a strong risk factor for developing Parkinson''s disease later in life and further research is required to determine if the observed abnormality in stimulant users is associated with a functional deficit of the nigro-striatal system.     

Endogenous ligands for sigma opioid receptors in the brain ("sigmaphin"): evidence from binding assays

Two endogenous ligands which interact preferentially with the sigma opioid receptors were identified from the guinea-pig brain extract in a Sephadex G-50 fractionation. These two ligands inhibited more potently the binding of [3H]SKF-10047 to sigma opioid receptors than [3H]naloxone to mu opioid receptors, [3H]ethylketocyclazocine to kappa opioid receptors and [3H]DADLE to delta opioid receptors. In the phencyclidine receptor assay, these two ligands were almost inactive. Incubation of these ligands with trypsin destroyed at least 50% of the activities in the sigma opioid receptor assay. Both ligands inhibited the sigma binding in a dose-dependent manner. The inhibition could be eliminated when the two ligands were removed from incubation media by extensive washings. It is therefore concluded that sigma opioid receptors are not phencyclidine receptors and that endogenous ligands for sigma opioid receptors may exist in the brain.     

Gas chromatographic-mass spectrometric analysis of residual solvent trapped into illicit cocaine exhibits using head-space solid-phase microextraction

The analysis of solvent residues trapped into crystals of illicit drugs provides useful evidence for monitoring current use trend in the chemical underground, and is also a suitable tool to achieve the complete chemical characterisation of street drugs for comparative examination of separate specimens. This paper describes a method developed in order to perform simultaneous qualitative and quantitative analysis of solvent residues in cocaine samples. The method is based on GC-MS analysis of solvents after their extraction/concentration from drug matrices accomplished by solid-phase microextraction (SPME) in static head space. The proposed method has been used to detect residues of solvents in 47 illicit street cocaine samples. Quantitative analyses were carried out only for the solvents identified at concentration values higher than 1 ppm. Statistical evaluation of our results allowed us to group the illicit samples into various classes according to different kinds of residual solvent, in connection with different clandestine manufacturing processes used to prepare illicit cocaine.     

Determination of oxcarbazepine and its metabolites in postmortem blood and hair by means of liquid chromatography with mass detection (HPLC/APCI/MS)

A typical use of hair analysis in forensic toxicology is the documentation of previous drug administration. This is illustrated in a suicidal death of a 58-year-old epileptic patient who was treated with oxcarbazepine and probably with levomepromazine. The toxicological analysis carried out by HPLC/APCI/MS included also the hair (6 cm length) besides postmortem blood. The method was validated for levomepromazine, oxcarbazepine (OXCBZ) and its two metabolites, 10-hydroxycarbazepine (CBZ-10OH) and trans-diol-carbazepine (CBZ-diOH) in various biological matrices. The analysis of the postmortem blood indicated oxcarbazepine and its two main metabolites were present at therapeutic concentrations; levomepromazine was detected at a fatal concentration. In three 2-cm segments of hair, oxcarbazepine and its two metabolites were detected; however, levomepromazine was not detected in this specimen. As a result of complex chemical-toxicological investigation it was confirmed the information that the decedent. was an epileptic patient and was treated with oxcarbazepine for at least 6 months before death. In addition, he took a toxic dose of levomepromazine in order to commit suicide. The analysis revealed differences between the concentration levels of oxcarbazepine and its active metabolite CBZ-10OH in postmortem specimens and hair, suggesting different mechanisms of penetration of metabolites and their precursors into this matrix.     

Simultaneous detection of amphetamine-like drugs with headspace solid-phase microextraction and gas chromatography-mass spectrometry

A headspace solid-phase microextraction and gas chromatography-mass spectrometry (HS-SPME-GC-MS) procedure for the simultaneous detection of methylen-dioxyamphetamine (MDA), methylen-dioxymethamphetamine (MDMA), methylen-dioxyethamphetamine (MDE) and N-methyl-1-(1,3-benzodioxol-5-yl)-2-butanamine (MBDB) in hair has been developed. This method is suitable for the separation of primary and secondary amines, is reproducible, is not time consuming, requires small quantities of sample and does not require any derivatization. It provides sufficient sensitivity and specificity, with limits of detection (LOD) and limits of quantitation (LOQ) for each substance of <0.7 and 1.90 ng/mg, respectively. Intra- and inter-day precision were within 2 and 10%, respectively. This method is suitable for routine clinical, epidemiological and forensic purposes and can be used for the preliminary screening of many other substances (amphetamine, methamphetamine, ketamine, ephedrine, nicotine, phencyclidine, methadone) in hair and other biological matrices such as saliva, urine and blood. We also describe the first application of this HS-SPME-GC-MS procedure to the analysis of hair and saliva samples from young people attending a disco in the Rome area. All positive hair samples were confirmed by the gas chromatography-mass-mass (GC-MS(2)) technique in positive chemical ionization (PCI) mode. Some examples of the use of the method in detecting different drugs are reported.     

The Global Epidemiology and Contribution of Cannabis Use and Dependence to the Global Burden of Disease: Results from the GBD 2010 Study

AimsEstimate the prevalence of cannabis dependence and its contribution to the global burden of disease.MethodsSystematic reviews of epidemiological data on cannabis dependence (1990-2008) were conducted in line with PRISMA and meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines. Culling and data extraction followed protocols, with cross-checking and consistency checks. DisMod-MR, the latest version of generic disease modelling system, redesigned as a Bayesian meta-regression tool, imputed prevalence by age, year and sex for 187 countries and 21 regions. The disability weight associated with cannabis dependence was estimated through population surveys and multiplied by prevalence data to calculate the years of life lived with disability (YLDs) and disability-adjusted life years (DALYs). YLDs and DALYs attributed to regular cannabis use as a risk factor for schizophrenia were also estimated.ResultsThere were an estimated 13.1 million cannabis dependent people globally in 2010 (point prevalence0.19% (95% uncertainty: 0.17-0.21%)). Prevalence peaked between 20-24 yrs, was higher in males (0.23% (0.2-0.27%)) than females (0.14% (0.12-0.16%)) and in high income regions. Cannabis dependence accounted for 2 million DALYs globally (0.08%; 0.05-0.12%) in 2010; a 22% increase in crude DALYs since 1990 largely due to population growth. Countries with statistically higher age-standardised DALY rates included the United States, Canada, Australia, New Zealand and Western European countries such as the United Kingdom; those with lower DALY rates were from Sub-Saharan Africa-West and Latin America. Regular cannabis use as a risk factor for schizophrenia accounted for an estimated 7,000 DALYs globally.ConclusionCannabis dependence is a disorder primarily experienced by young adults, especially in higher income countries. It has not been shown to increase mortality as opioid and other forms of illicit drug dependence do. Our estimates suggest that cannabis use as a risk factor for schizophrenia is not a major contributor to population-level disease burden.     

Drinking,smoking, and illicit drug use among 15 and 16 year olds in the United Kingdom.

OBJECTIVE: To examine patterns of self reported drinking, smoking, and illicit drug use among a representative United Kingdom sample of people born in 1979. DESIGN: Cross sectional, single phase survey based on a stratified cluster sample of 70 United Kingdom secondary schools during March and April 1995. Pupils completed a 406 item standardised questionnaire under examination conditions. SETTING: United Kingdom state and private secondary schools. SUBJECTS: 7722 pupils aged 15 and 16. MAIN OUTCOME MEASURES: Reported use of alcohol, tobacco, and illicit drugs. RESULTS: Almost all the pupils had drunk alcohol, 36% (2772/7689) had smoked cigarettes in the past 30 days, and 42.3% (3264/7722) had at some time used illicit drugs, mainly cannabis. 43% (1546/3546) of boys and 38% (1529/4009) of girls had tried cannabis. Higher levels of smoking were associated with poorer school performance (20.4% (783/3840) with average performance v 44.1% (214/486) with below average performance, F = 79.06, P < 0.01). Levels of drug use in 15 and 16 year olds in 1995 were higher in Scotland than in England, Wales, or Northern Ireland. CONCLUSIONS: Drug experimentation was high among 15 and 16 year olds, and use of cannabis was particularly high among smokers. Cigarette smoking was more common among girls than boys.     

Hair analysis for abused and therapeutic drugs

This review focuses on basic aspects and recent studies of hair analysis for abused and therapeutic drugs and is discussed with 164 references. Firstly, biology of hair and sampling of hair specimens have been commented for the sake of correct interpretation of the results from hair analysis. Then the usual washing methods of hair samples and the extraction methods for drugs in hair have been shown and commented on. Analytical methods for each drug have been discussed by the grouping of three analytical methods, namely immunoassay, HPLC–CE and GC–MS. The outcomes of hair analysis studies have been reviewed by dividing into six groups; morphine and related, cocaine and related, amphetamines, cannabinoids, the other abused drugs and therapeutic drugs. In addition, reports on stability of drugs in the living hair and studies on drug incorporation into hair and dose–hair concentration relationships have been reviewed. Applications of hair analysis to the estimation of drug history, discrimination between OTC drug use and illegal drug use, drug testing for acute poisoning, gestational drug exposure and drug compliance have also been reviewed. Finally, the promising prospects of hair analysis have been described.     

Illicit Stimulant Use in Humans Is Associated with a Long-Term Increase in Tremor

Use of illicit stimulants such as methamphetamine, cocaine, and ecstasy is a significant health problem. The United Nations Office on Drugs and Crime estimates that 14–57 million people use stimulants each year. Chronic use of illicit stimulants can cause neurotoxicity in animals and humans but the long-term functional consequences are not well understood. Stimulant users self-report problems with tremor whilst abstinent. Thus, the aim of the current study was to investigate the long-term effect of stimulant use on human tremor during rest and movement. We hypothesized that individuals with a history of stimulant use would exhibit abnormally large tremor during rest and movement. Tremor was assessed in abstinent ecstasy users (n = 9; 22±3 yrs) and abstinent users of amphetamine-like drugs (n = 7; 33±9 yrs) and in two control groups: non-drug users (n = 23; 27±8 yrs) and cannabis users (n = 12; 24±7 yrs). Tremor was measured with an accelerometer attached to the index finger at rest (30 s) and during flexion and extension of the index finger (30 s). Acceleration traces were analyzed with fast-Fourier transform. During movement, tremor amplitude was significantly greater in ecstasy users than in non-drug users (frequency range 3.9–13.3 Hz; P<0.05), but was unaffected in cannabis users or users of amphetamine-like drugs. The peak frequency of tremor did not significantly differ between groups nor did resting tremor. In conclusion, abstinent ecstasy users exhibit an abnormally large tremor during movement. Further work is required to determine if the abnormality translates to increased risk of movement disorders in this population.     

Increased risk for COVID‐19 breakthrough infection in fully vaccinated patients with substance use disorders in the United States between December 2020 and August 2021

Individuals with substance use disorders (SUDs) are at increased risk for COVID‐19 infection and for adverse outcomes of the infection. Though vaccines are highly effective against COVID‐19, their effectiveness in individuals with SUDs might be curtailed by compromised immune status and a greater likelihood of exposures, added to the waning vaccine immunity and the new SARS‐CoV‐2 variants. In a population‐based cohort study, we assessed the risk, time trends, outcomes and disparities of COVID‐19 breakthrough infection in fully vaccinated SUD patients starting 14 days after completion of vaccination. The study included 579,372 individuals (30,183 with a diagnosis of SUD and 549,189 without such a diagnosis) who were fully vaccinated between December 2020 and August 2021, and had not contracted COVID‐19 infection prior to vaccination. We used the TriNetX Analytics network platform to access de‐identified electronic health records from 63 health care organizations in the US. Among SUD patients, the risk for breakthrough infection ranged from 6.8% for tobacco use disorder to 7.8% for cannabis use disorder, all significantly higher than the 3.6% in non‐SUD population (p<0.001). Breakthrough infection risk remained significantly higher after controlling for demographics (age, gender, ethnicity) and vaccine types for all SUD subtypes, except for tobacco use disorder, and was highest for cocaine and cannabis use disorders (hazard ratio, HR=2.06, 95% CI: 1.30‐3.25 for cocaine; HR=1.92, 95% CI: 1.39‐2.66 for cannabis). When we matched SUD and non‐SUD individuals for lifetime comorbidities and adverse socioeconomic determinants of health, the risk for breakthrough infection no longer differed between these populations, except for patients with cannabis use disorder, who remained at increased risk (HR=1.55, 95% CI: 1.22‐1.99). The risk for breakthrough infection was higher in SUD patients who received the Pfizer than the Moderna vaccine (HR=1.49, 95% CI: 1.31‐1.69). In the vaccinated SUD population, the risk for hospitalization was 22.5% for the breakthrough cohort and 1.6% for the non‐breakthrough cohort (risk ratio, RR=14.4, 95% CI: 10.19‐20.42), while the risk for death was 1.7% and 0.5% respectively (RR=3.5, 95% CI: 1.74‐7.05). No significant age, gender and ethnic disparities for breakthrough infection were observed in vaccinated SUD patients. These data suggest that fully vaccinated SUD individuals are at higher risk for breakthrough COVID‐19 infection, and this is largely due to their higher prevalence of comorbidities and adverse socioeconomic determinants of health compared with non‐SUD individuals. The high frequency of comorbidities in SUD patients is also likely to contribute to their high rates of hospitalization and death following breakthrough infection.     

Buprenorphine detoxification from opioid dependence: a pilot study

Sixteen opioid dependent patients were assigned to treatment with buprenorphine for one month at three doses--2 mg (n = 10), 4 mg (n = 4), 8 mg (n = 2). Treatment retention was excellent--only one patient left due to withdrawal symptoms. Illicit opioid use was infrequent, with only 22% of the urines containing illicit opioids. Although buprenorphine dose was not associated with retention or illicit opioid use, patterns of withdrawal symptoms differed among dosage groups during the 30 day study. The 4 mg group had a substantial decline in symptoms, while the other two groups did not. Symptom levels were comparable to those during successful clonidine detoxification and much lower than those found in clonidine failures.     

Drug testing in oral fluid

Over the last decade there have been considerable developments in the use of oral fluid (saliva) for drug testing. Oral fluid can provide a quick and non-invasive specimen for drug testing. However, its collection may be thwarted by lack of available fluid due to a range of physiological factors, including drug use itself. Food and techniques designed to stimulate production of oral fluid can also affect the concentration of drugs. Current applications are mainly focused on drugs of abuse testing in employees at workplaces where drug use has safety implications, in drivers of vehicles at the roadside and in other situations where drug impairment is suspected. Testing has included alcohol (ethanol) and a range of clinical tests eg antibodies to HIV, therapeutic drugs and steroids. Its main application has been for testing for drugs of abuse such as the amphetamines, cocaine and metabolites, opioids such as morphine, methadone and heroin, and for cannabis. Oral fluid concentrations of basic drugs such as the amphetamines, cocaine and some opioids are similar or higher than those in plasma. Tetrahydrocannabinol (THC), the major species present from cannabis use, displays similar concentrations in oral fluid compared to blood in the elimination phase. However, there is significant local absorption of the drug in the oral cavity which increases the concentrations for a period after use of drug. Depot effects occur for other drugs introduced into the body that allow local absorption, such as smoking of tobacco (nicotine), cocaine, amphetamines, or use of sub-lingual buprenorphine. Screening techniques are usually an adaptation of those used in other specimens, with an emphasis on the parent drug since this is usually the dominant species present in oral fluid. Confirmatory techniques are largely based on mass spectrometry (MS) with an emphasis on Liquid Chromatography-Mass Spectrometry (LC-MS), due to low sample volumes and the low detection limits required. Drug testing outside laboratory environments has become widespread and provides presumptive results within minutes of collection of specimens. This review focuses on the developments, particularly over the last 10 years, and outlines the roles and applications of testing for drugs in oral fluid, describes the difficulties associated with this form of testing and illustrates applications of oral fluid testing for specific drugs.