Recreational Ketamine Users Research Articles

Participants’ experiences of ketamine bladder syndrome: A qualitative study

The aim of this study is to explore recreational ketamine users’ experiences of ketamine bladder syndrome (KBS) and related health care provision issues. KBS is an emerging condition caused by chronic, recreational ketamine use, which can result in extensive, irreparable damage to the bladder and urinary tract. However, little is yet known about how patients are personally affected by the condition, their help seeking behaviour or experiences of related health care services. A qualitative study, informed by Heideggerian hermeneutics was undertaken. Twelve participants affected by KBS were purposively recruited into the study from an National Health Service (NHS) continence service and a drug support agency in South Wales, UK. Data were collected through recorded, semi‐structured interviews and analysed using a three‐step approach. Participants were predominantly younger, poly‐drug users and typically developed KBS following prolonged, habitual ketamine use. The effects of KBS were considerable and included incontinence, haematuria, profound abdominal pain and embarrassment and were exacerbated by delays in help seeking, disjointed medical care and on‐going ketamine use, which was integral to the self‐management of KBS pain. KBS has significant impact on those affected and can result in extensive, irreversible damage to the bladder and urinary tract. The condition, and its management, is further compounded by chronic poly‐drug use, chaotic lifestyles and a range of complex, related co‐morbidities, which require a collaborative, multi‐disciplinary approach. Anderson's behavioural model of health services use provides an appropriate framework for better understanding help seeking/avoidance behaviour in this cohort, which can help inform clinical practice.

Patterns of use, harm reduction strategies, and their relation to risk behavior and harm in recreational ketamine users

ABSTRACTBackground: Recent studies have shown that ketamine use has serious adverse consequences. However, no studies have focused on the strategies that users carry out to protect themselves from such potential harm. Objectives: (i) analyze harm reduction strategies, risk behaviors, and harms in nonmedical/recreational ketamine users; (ii) analyze the association of their harm reduction strategies and risk behaviors with harms they report. Methods: An anonymous cross-sectional web-based survey of 462 persons who had used ketamine in the past year. We designed a questionnaire to collect information on their risk behaviors, harm, and harm reduction strategies. Results: The harms most reported were unexpected confusion (58.2%), memory impairment (57.4%), and abrupt mood/behavior changes (49.6%). The most frequent strategies were spacing out sessions (60.8% always/almost always did this), spacing out doses within a session (54.5%), and limiting the amount and not going over it (41.3%). The use of these three strategies was related to a lower probability of perceiving negative consequences associated with ketamine use, including memory impairment, healthcare assistance, psychological dependence, and risk behaviors related to driving under the influence of ketamine. Conclusions: This study provides empirical evidence on strategies related to the lower probability of harm associated with ketamine use as employed by recreational ketamine users. Our findings suggest that efforts to minimize harm from ketamine use should focus on increasing awareness of potential harms and the use of identified harm reduction strategies.

Reliability, convergent and structural validity and cut-off score of the Severity of Dependence Scale for recreational ketamine users

Background and aimsThere is a lack of instruments for measuring ketamine substance use disorders. The aims were (i) to estimate the reliability and provide evidence of validity of the Severity of Dependence Scale (SDS) in a sample of recreational users, and (ii) propose a cut-off point to determine the presence of dependence. MethodsWe conducted a web-based cross-sectional survey with recreational users who accessed webs related to recreational drug use and harm reduction. 264 recreational ketamine users who had taken it in the past month participated in the study. The Spanish version of the SDS was used. Information on ketamine use-related problems and ketamine use patterns was also collected. ResultsThe reliability estimation calculated by the Cronbach’s alpha coefficient was 0.776. SDS showed evidence of convergent validity based on relationships with other variables. Two comparisons were made in this study to analyze the Receiver Operating Characteristic Curve. For frequency of use in the last month the area under curve (AUC) was 0.835 (CI=0.775-0.895) with optimal discrimination at an SDS score of 3. For having been in treatment for decreasing or quitting ketamine use the AUC was 0.902 (CI=0.840-0.963) and the cut-off point was 4. Confirmatory factor analysis showed a one-dimensional structure when Items 3 and 4 were correlated. ConclusionsThis study has provided evidence of reliability and validity of the ketamine version of the SDS for recreational users. Considering that ketamine use is linked to young people and its strong potential for causing serious impairment, a cut-off of 3 is proposed as indicative of dependence.

Elevated Serum IgE May be Associated with Development of Ketamine Cystitis

Previous studies revealed bladder mast cell and eosinophil cell infiltration in patients with ketamine cystitis. Due to possible hypersensitivity in those with this condition we investigated the association of serum Ig, histology findings and symptoms in patients with ketamine cystitis. We evaluated patients with ketamine cystitis for maximal bladder capacity, serum IgE, IgG and IgM, and pain visual analog scale score. Bladder biopsies were assessed for mast cells and eosinophils. Patients with interstitial cystitis/bladder pain syndrome, acute bacterial cystitis and controls were also studied. We used the Mann-Whitney U test for nonparametric data to compare serum IgE among groups with p <0.017 considered significant. Median serum IgE was significantly higher in the 20 patients withketamine cystitis (205.5 IU/ml, IQR 36.9, 514.0) than in the 10 controls (33.4 IU/ml, IQR 13.5, 71.7, p = 0.015) and the 15 with acute bacterial cystitis (34.6 IU/ml, IQR 24.2, 101.9, p = 0.015). It was marginally higher than in the 13patients withinterstitial cystitis/bladder pain syndrome (65.8 IU/ml, IQR 11.9, 133.0, p = 0.029). Of patients with ketamine cystitis the median visual analog scale pain score was significantly higher in those with serum IgE greater than compared to less than 200 IU/ml. Maximal bladder capacity was significantly less in patients with ketamine cystitis who had higher IgE. Patients with severe or moderate bladder eosinophil infiltration had a greater visual analog scale score, higher serum IgE and smaller maximal bladder capacity than patients with no or mild eosinophil infiltration. Serum IgE and the visual analog scale score correlated significantly (r(2) = 0.318, p = 0.01). Patients with ketamine cystitis had higher serum IgE than patients with interstitial cystitis/bladder pain syndrome or acute bacterial cystitis, or controls. Serum IgE and the severity of eosinophil infiltration were associated with bladder pain severity and small maximal bladder capacity.

Dependence and urinary symptoms among recreational ketamine users

Dependence and urinary symptoms among recreational ketamine users

The prevalence and natural history of urinary symptoms among recreational ketamine users

The prevalence and natural history of urinary symptoms among recreational ketamine users

THE PREVALENCE AND NATURAL HISTORY OF URINARY SYMPTOMS AMONG RECREATIONAL KETAMINE USERS

Study Type – Symptom prevalence (prospective cohort) Level of Evidence 1b What's known on the subject? and What does the study add? Case series have described lower urinary tract symptoms associated with ketamine use including severe pain, frequency, haematuria and dysuria. Little is known regarding the frequency of symptoms, relationship of symptoms with dose and frequency of use and natural history of symptoms once the ketamine user has stopped. This study describes the prevalence of ketamine use in a population of recreational drug users in a dance music setting. It shows a dose–frequency relationship with ketamine use. It shows that urinary symptoms associated with recreational ketamine use may lead to a considerable demand on health resources in the primary-, secondary- and emergency-care settings. It shows that symptoms may improve once ketamine use is decreased. OBJECTIVE • To investigate the prevalence and natural history of urinary symptoms in a cohort of recreational ketamine users. PATIENTS AND METHODS • A purposeful sampling technique was used. • Between November 2009 and January 2010 participants were invited to undertake an on-line questionnaire promoted by a national dance music magazine and website. • Data regarding demographics and illicit drug-use were collected. • Among respondents reporting recent ketamine use, additional information detailing their ketamine use, experience of urinary symptoms and use of related healthcare services was obtained. RESULTS • In all, 3806 surveys were completed, of which 1285 (33.8%) participants reported ketamine use within the last year. • Of the ketamine users, 17% were found to be dependent on the drug; 26.6% (340) of recent ketamine users reported experiencing urinary symptoms. • Urinary symptoms were significantly related to both dose of ketamine used and frequency of ketamine use. • Of 251 users reporting their experience of symptoms over time in relationship to their use of ketamine, 51% reported improvement in urinary symptoms upon cessation of use with only eight (3.8%) reporting deterioration after stopping use. CONCLUSIONS • Urinary tract symptoms are reported in over a quarter of regular ketamine users. • A dose and frequency response relationship has been shown between ketamine use and urinary symptoms. • Both users and primary-care providers need to be educated about urinary symptoms that may arise in ketamine users. A multi-disciplinary approach promoting harm reduction, cessation and early referral is needed to manage individuals with ketamine-associated urinary tract symptoms to avoid progression to severe and irreversible urological pathologies.

The prevalence and natural history of urinary symptoms among recreational ketamine users

Study Type--Symptom prevalence (prospective cohort) Level of Evidence 1b. What's known on the subject? and What does the study add? Case series have described lower urinary tract symptoms associated with ketamine use including severe pain, frequency, haematuria and dysuria. Little is known regarding the frequency of symptoms, relationship of symptoms with dose and frequency of use and natural history of symptoms once the ketamine user has stopped. This study describes the prevalence of ketamine use in a population of recreational drug users in a dance music setting. It shows a dose-frequency relationship with ketamine use. It shows that urinary symptoms associated with recreational ketamine use may lead to a considerable demand on health resources in the primary-, secondary- and emergency-care settings. It shows that symptoms may improve once ketamine use is decreased. • To investigate the prevalence and natural history of urinary symptoms in a cohort of recreational ketamine users. • A purposeful sampling technique was used. • Between November 2009 and January 2010 participants were invited to undertake an on-line questionnaire promoted by a national dance music magazine and website. • Data regarding demographics and illicit drug-use were collected. • Among respondents reporting recent ketamine use, additional information detailing their ketamine use, experience of urinary symptoms and use of related healthcare services was obtained. • In all, 3806 surveys were completed, of which 1285 (33.8%) participants reported ketamine use within the last year. • Of the ketamine users, 17% were found to be dependent on the drug; 26.6% (340) of recent ketamine users reported experiencing urinary symptoms. • Urinary symptoms were significantly related to both dose of ketamine used and frequency of ketamine use. • Of 251 users reporting their experience of symptoms over time in relationship to their use of ketamine, 51% reported improvement in urinary symptoms upon cessation of use with only eight (3.8%) reporting deterioration after stopping use. • Urinary tract symptoms are reported in over a quarter of regular ketamine users. • A dose and frequency response relationship has been shown between ketamine use and urinary symptoms. • Both users and primary-care providers need to be educated about urinary symptoms that may arise in ketamine users. A multi-disciplinary approach promoting harm reduction, cessation and early referral is needed to manage individuals with ketamine-associated urinary tract symptoms to avoid progression to severe and irreversible urological pathologies.

Anomalous bodily-self experiences among recreational ketamine users

Introduction. Out-of-body experiences present a unique paradigm to investigate cognitive and neural mechanisms of bodily-self processes and their disorders. Previous work on out-of-body experiences associated with sleep paralysis supported a model in which illusory movement experiences reflect disrupted bodily-self integration generating anomalous vestibular and motor sensations. Further disintegration and progression of the experience may then give rise to out-of-body feelings, which in turn may instigate out-of-body autoscopy. Methods. The current study assesses the disintegration model through analyses of out-of-body experiences reports from an online survey of individuals reporting recreational ketamine use (n=128) and cross-validation in a sample of nonketamine polydrug users (n=64). Path analyses using intensity and frequency measures of anomalous experiences assess the fit of seven competing models. Results. The disintegration model (illusory movement → out-of-body feelings → out-of-body autoscopy) emerged as the best fitting model overall and results support full mediation of the relation between illusory movement experiences and out-of-body autoscopy by out-of-body feelings. Moreover, lifetime measures of ketamine use predicted the frequency of illusory movement experiences. Conclusions. The results corroborate this structural model of out-of-body phenomena and encourage a framework for future studies into aetiological mechanisms of out-of-body experiences to include neurochemical systems.

Cystitis and ketamine-associated bladder dysfunction

ObjectivesTo analyze the prevalence of lower urinary tract symptoms (LUTS) in recreational ketamine users and evaluate its relationship with the consumption pattern. Material and methodsEvaluation of 13 ketamine users. The presence of LUTS, gross hematuria and lumbar spine pain was analyzed. The ketamine usage pattern was recorded: initiation, administration route, dose in the last month, and frequency of usage. ResultsSix patients (46%) reported LUTS, with daily mean micturations every 42min and nighttime of 3 episodes, with dysuria (100%), urgency (100%), incontinence (20%), decreased flow (80%), hypogastric or perineal pain (80%), gross hematuria (80%) and bilateral lumbar spine pain (40%). Symptomatic patients described a mean intake of inhaled ketamine of 3g/day (SD 2), 80% with a daily frequency and the asymptomatic ones of 1.03g/day (SD 0.92) limited to weekends. The mean consumption time to the appearance of the symptoms was 31 months (SD 16.29). Intensity of the symptoms was related with the ketamine dose and improved on increasing water intake. ConclusionsThere seems to be a relationship between the picture with the dose and frequency of consumption, there being factors that reinforce the hypothesis that this action of the drug is due to the harmful effect on the urothelium. The process to identify it on time should be known, since the only known effective measure is to stop the consumption in the initial phases.

Ketamine-snorting associated cystitis

Ketamine hydrochloride, commonly used as a pediatric anesthetic agent, is an N-methyl-D-aspartic (NMDA) acid receptor antagonist with rapid onset and short duration of action. It produces a cataleptic-like state where the patient is dissociated from the surrounding environment by direct action on the cortex and limbic system. It has emerged as an increasingly popular choice among young drug users, especially within dance club venues. Cases of bladder dysfunction among recreational ketamine users were reported since Shahani et al first reported nine cases of ketamine-associated ulcerative cystitis in 2007. We report on four patients who had history of ketamine abuse, presenting with dysuria, fluctuating lower urinary tract symptoms (LUTS), lower abdominal or perineal pain, and impaired functional bladder capacities. Urinalysis showed pyuria and microhematuria. Urine culture was sterile. Bladder ulceration with severe diffuse hemorrhage and low bladder capacity were noted under anesthetized cystoscopic examination. Transurethral bladder mucosa biopsy was consistent with chronic cystitis. Cessation of ketamine abuse was the milestone of treatment, followed by the administration of mucosal protective agents, such as pentosan polysulphate or hyaluronic acid. Suprapubic pain was improved in three patients during follow-up. However, the outcome of treatment depends on the severity of the disease process, similar to that of interstitial cystitis (IC).

Cistitis y disfunción vesical asociada al consumo de ketamina

Objectives To analyze the prevalence of lower urinary tract symptoms (LUTS) in recreational ketamine users and evaluate its relationship with the consumption pattern. Material and methods Evaluation of 13 ketamine users. The presence of LUTS, gross hematuria and lumbar spine pain was analyzed. The ketamine usage pattern was recorded: initiation, administration route, dose in the last month and frequency of usage. Results Six patients (46%) reported LUTS, with daily mean micturations every 42 minutes and nighttime of 3 episodes, with dysuria (100%), urgency (100%), incontinence (20%), decreased flow (80%), hypogastric or perineal pain (80%), gross hematuria (80%) and bilateral lumbar spine pain (40%). Symptomatic patients described a mean intake of inhaled ketamine of 3 g/day (SD 2), 80% with a daily frequency and the asymptomatic ones of 1.03 g/day (SD 0.92) limited to weekends. The mean consumption time to the appearance of the symptoms was 31 months (SD 16.29). Intensity of the symptoms was related with the ketamine dose and improved on increasing water intake. Conclusions There seems to be a relationship between the picture with the dose and frequency of consumption, there being factors that reinforce the hypothesis that this action of the drug is due to the harmful effect on the urothelium. The process to identify it on time should be known, since the only known effective measure is to stop the consumption in the initial phases.

Acute and Chronic Effects of Ketamine on Semantic Priming

Acute administration of the N-methyl-D-aspartate receptor antagonist ketamine induces schizophrenia-like symptoms in healthy volunteers; furthermore, a window on ketamine's chronic effects is provided by regular recreational users. The current study utilized both acute ketamine administration in healthy volunteers and chronic ketamine abusers to investigate semantic processing, one of the key cognitive deficits in schizophrenia. Semantic processing was examined using a semantic priming paradigm. In experiment 1, acute effects of low (75 ng/mL) and high (150 ng/mL) ketamine doses were compared in a placebo-controlled double-blind independent group design with 48 participants. In experiment 2, 19 regular recreational ketamine users were compared with 19 ketamine-naive polydrug controls and 26 non-drug-using controls. In both experiments, semantic priming parameters were manipulated to distinguish between ketamine's effects on (1) automatic and strategic processing and (2) the facilitation and inhibition components of semantic priming for strongly (directly) related primes and targets. Acute effects of ketamine on semantic priming for weakly (indirectly) related primes and targets were also assessed in experiment 1. Acutely, ketamine impaired the employment of strategic mechanisms but not automatic processing within both the direct and indirect semantic priming tasks. Acute ketamine administration also induced clear schizophrenia-like symptoms. Schizotypy traits in the cognitive and perceptual domains tended to correlate with increased semantic priming in long-term ketamine users. In summary, acute and chronic ketamine-induced changes partially mirrored the findings on semantic priming in schizophrenia.

Ketamine-Associated Ulcerative Cystitis: A New Clinical Entity

Ketamine hydrochloride is an N-methyl-D-aspartic acid receptor antagonist used as an anesthetic agent in human and veterinary procedures. Increasingly, it is being used as a recreational drug. Recreational ketamine users have anecdotally reported increased lower urinary tract symptoms while using the substance. We describe a series of 9 patients, all of whom were daily ketamine users, who presented with severe dysuria, frequency, urgency, and gross hematuria. Investigations, including urine culture, microscopy, and cytology, in addition to computed tomography, cystoscopy, and bladder biopsies, were performed to identify a relationship between recreational ketamine use and these symptoms. The urine cultures were sterile in all cases. Computed tomography revealed marked thickening of the bladder wall, a small capacity, and perivesicular stranding, consistent with severe inflammation. At cystoscopy, all patients had severe ulcerative cystitis. Biopsies in 4 patients revealed epithelial denudation and inflammation with a mild eosinophilic infiltrate. Cessation of ketamine use, with the addition of pentosan polysulfate, appeared to provide some symptomatic relief. This case series has described a new clinical entity of severe ulcerative cystitis as a result of chronic ketamine use. As illicit ketamine becomes more easily available, ulcerative cystitis and potential long-term bladder sequelae related to its use may be a more prevalent problem confronting urologists.

Altered Prefrontal Dopaminergic Function in Chronic Recreational Ketamine Users

Altered Prefrontal Dopaminergic Function in Chronic Recreational Ketamine Users

Altered Prefrontal Dopaminergic Function in Chronic Recreational Ketamine Users

Ketamine is a noncompetitive antagonist at the glutamatergic N-methyl-D-aspartate (NMDA) receptor that is used in human and animal medicine as an injectable anesthetic. The illegal use of ketamine as a recreational drug is rapidly growing. Very little is currently known about the consequences of repeated ketamine exposure in the human brain. Animal studies indicate that the prefrontal dopaminergic system is particularly vulnerable to the toxic effects of repeated administration of NMDA antagonists. In this study, dopamine D1 receptor availability was assessed by using positron emission tomography and the selective D1 receptor radioligand [11C]NNC 112 in a group of 14 recreational chronic ketamine users and matched healthy subjects. History of ketamine abuse was confirmed in subjects by hair analysis. [11C]NNC 112 binding potential was measured with kinetic analysis using the arterial input function. Dorsolateral prefrontal cortex D1 receptor availability was significantly up-regulated in chronic ketamine users ([11C]NNC 112 binding potential: mean=1.68 ml/g, SD=0.40) relative to comparison subjects (mean=1.35 ml/g, SD=0.35). No significant differences were noted in other cortical, limbic, or striatal regions. In the chronic ketamine user group, dorsolateral prefrontal cortex [11C]NNC 112 binding potential up-regulation was significantly correlated with the number of vials of ketamine (with a vial representing approximately 200-300 mg of ketamine) used per week. Chronic ketamine users exhibited a regionally selective up-regulation of D1 receptor availability in the dorsolateral prefrontal cortex, a phenomenon observed following chronic dopamine depletion in animal studies. These data suggest that the repeated use of ketamine for recreational purposes affects prefrontal dopaminergic transmission, a system critically involved in working memory and executive function.

The health and psycho-social consequences of ketamine use

Ketamine is a non-competitive NMDA receptor antagonist that acts as a dissociative anaesthetic with analgesic and amnestic properties. Ketamine has broad areas of application and is a rapidly acting, relatively safe analgesic and anaesthetic agent, particularly for children and is widely used in veterinary practice. Ketamine can induce schizophrenic-like symptoms in healthy adults and schizophrenic patients. It has a wide margin of safety and there are very few cases of pure ketamine overdose recorded, with the majority of deaths due to the dangerous activities or contexts of its use. Information on ketamine is not routinely collected in population surveys and morbidity and mortality data collections. Levels of use in the general population, however, appear to be very low with higher levels in groups with access to the drug, medical and veterinarian professionals, and party drug users. There are a number of potential ketamine effects that may be seen as adverse or harmful, with growing evidence of the physical and psychological symptoms of ketamine dependence among recreational ketamine users. A withdrawal syndrome, including psychotic features, is beginning to be described. The use of ketamine with other neurotoxic drugs, such as alcohol, should be avoided. Increased rates of high risk sexual and injecting behaviours in association with ketamine use, however, have been reported by gay men and marginalised youth in the US. In conclusion, ketamine does not appear to currently pose a significant public health risk, however, at the individual level the usual harm minimisation strategies should be observed.

Beyond the K‐hole: a 3‐year longitudinal investigation of the cognitive and subjective effects of ketamine in recreational users who have substantially reduced their use of the drug

Ketamine is a dissociative anaesthetic that is also a drug of abuse. Previous studies have demonstrated persisting episodic and semantic memory impairments in recreational ketamine users 3 days after taking ketamine. However, the degree to which these deficits might be reversible upon reduction or cessation of ketamine use was not known. To follow-up a population of ketamine users tested 3 years previously and examine whether impairments observed 3 days after drug use are enduring or reversible. Eighteen ketamine users and 10 polydrug controls from studies conducted between 3 and 4 years earlier were re-tested on the same battery of cognitive tasks and subjective measures. These tapped episodic, semantic and working memory and executive and attentional functioning. Subjective schizotypal, dissociative, mood and bodily symptoms were also examined and a drug use history recorded. The ketamine users had reduced their frequency of use of ketamine by an average of 88.3%. Performance of ketamine users on tasks tapping semantic memory had improved and this improvement was correlated with their reduction in ketamine use. On tasks tapping episodic memory and attentional functioning, ketamine users still showed deficits compared to polydrug controls. Higher levels of schizotypal symptoms and perceptual distortions were exhibited by the ketamine group, although dissociative symptoms were similar to controls. These findings indicate that semantic memory impairments associated with recreational ketamine are reversible upon marked reduction of use; however, impairments to episodic memory and possibly attentional functioning appear long-lasting. In addition, schizotypal symptoms and perceptual distortions may persist after cessation of ketamine use. Ketamine users, or potential users, should be aware of the enduring effects of this drug on aspects of memory and subjective experience.