Diagnostic and Statistical Manual of Mental Disorders, 4th ed

This review provides a critical analysis of the central nervous system effects of acute and chronic methamphetamine (MA) use, which is linked to numerous adverse psychosocial, neuropsychiatric, and medical problems. A meta-analysis of the neuropsychological effects of MA abuse/dependence revealed broadly medium effect sizes, showing deficits in episodic memory, executive functions, information processing speed, motor skills, language, and visuoconstructional abilities. The neuropsychological deficits associated with MA abuse/dependence are interpreted with regard to their possible neural mechanisms, most notably MA-associated frontostriatal neurotoxicity. In addition, potential explanatory factors are considered, including demographics (e.g., gender), MA use characteristics (e.g., duration of abstinence), and the influence of common psychiatric (e.g., other substance-related disorders) and neuromedical (e.g., HIV infection) comorbidities. Finally, these findings are discussed with respect to their potential contribution to the clinical management of persons with MA abuse/dependence.

Neurocognitive Effects of Methamphetamine: A Critical Review and Meta-analysis

Aims To examine the literature regarding clinical pharmacokinetics, direct effects and adverse clinical outcomes associated with methamphetamine use.

Methods  Relevant literature was identified through a PubMed search. Additional literature was obtained from relevant books and monographs.

Findings and conclusions  The mean elimination half-life for methamphetamine is approximately 10 hours, with considerable inter-individual variability in pharmacokinetics. Direct effects at low-to-moderate methamphetamine doses (5–30 mg) include arousal, positive mood, cardiac stimulation and acute improvement in cognitive domains such as attention and psychomotor coordination. At higher doses used typically by illicit users (≥50 mg), methamphetamine can produce psychosis. Its hypertensive effect can produce a number of acute and chronic cardiovascular complications. Repeated use may induce neurotoxicity, associated with prolonged psychiatric symptoms, cognitive impairment and an increased risk of developing Parkinson's disease. Abrupt cessation of repeated methamphetamine use leads to a withdrawal syndrome consisting of depressed mood, anxiety and sleep disturbance. Acute withdrawal lasts typically for 7–10 days, and residual symptoms associated with neurotoxicity may persist for several months.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1360-0443.2009.02564.x

A review of the clinical pharmacology of methamphetamine.

Issues. The major physical and psychological health effects of methamphetamine use, and the factors associated with such harms. Approach. Comprehensive review. Key Findings. Physical harms reviewed...

Major physical and psychological harms of methamphetamine use

Polydrug abuse: A review of opioid and benzodiazepine combination use

Aims To characterize the natural history of methamphetamine withdrawal during the first 3 weeks of abstinence. Design Cross-sectional study with comparison group. Setting A substance use treatment facility in Chiang Mai Province, Thailand. Participants The sample comprised 21 in-patients undergoing treatment for methamphetamine dependence. Nine age- and sex-matched non-dependent individuals provided comparison data. Measurements Instruments including: the Amphetamine Withdrawal Ques- tionnaire, a modified version of the Cocaine Selective Severity Assessment, Clin- ical Global Impression scale and the St Mary's Hospital Sleep Questionnaire were completed daily for the first 3 weeks of abstinence. Findings Methamphetamine withdrawal severity declined from a high initial peak within 24 hours of the last use of amphetamines reducing to near control levels by the end of the first week of abstinence (the acute phase). The acute phase of amphetamine withdrawal was characterized by increased sleeping and eating, a cluster of depression-related symptoms and less severely, anxiety and craving-related symptoms. Following the acute withdrawal phase most with- drawal symptoms remained stable and at low levels for the remaining 2 weeks of abstinence. Conclusions This study has provided evidence of a methamphetamine with- drawal syndrome that can be categorized into two phases, the acute phase last- ing 7-10 days during which overall symptom severity declined in a linear pattern from a high initial peak, and a subacute phase lasting at least a further 2 weeks.

The nature, time course and severity of methamphetamine withdrawal.

AIMS: To ascertain the prevalence and risk factors for non-fatal overdose among heroin users to assist in the development of an effective intervention. DESIGN: Cross-sectional design. SETTING: Community setting, principally metropolitan Adelaide. PARTICIPANTS: Current heroin users (used heroin in the previous six months). MEASUREMENTS: A structured questionnaire including the Severity of Dependence Scale. FINDING: Of 218 current South Australian heroin users interviewed in 1996, 48% had experienced at least one non-fatal overdose their life-time (median: two overdoses), and 11% had overdosed in the previous 6 months. At some time, 70% had been present at someone else's overdose (median: three overdoses). At the time of their own most recent overdose, 52% had been using central nervous system depressants in addition to heroin, principally benzodiazepines (33%) and/or alcohol (22%). The majority of overdoses occurred in a private home (81%) and in the presence of other people (88%). Unrealistic optimism regarding the risk of overdose was evident across the sample. Despite almost half the sample reporting having had an overdose, and the belief expressed by respondents that on average about 50% of regular heroin users would overdose during their life-time 73% had, during the previous 6 months, "rarely" or "never" worried about possibly overdosing. Optimism regarding the possibility of future overdose was reduced in those with recent experience of overdose in comparison to the rest of the sample. A targeted intervention aimed at the reduction of overdose among heroin users is outlined. Language: en

Experience of non-fatal overdose among heroin users in Adelaide, Australia: circumstances and risk perceptions

Symptoms and sleep patterns during inpatient treatment of methamphetamine withdrawal: A comparison of mirtazapine and modafinil with treatment as usual

A comparison of antagonist-precipitated withdrawal under anesthesia to standard inpatient withdrawal as a precursor to maintenance naltrexone treatment in heroin users: outcomes at 6 and 12 months.

Fixed and symptom-triggered taper methods during in-patient benzodiazepine withdrawal treatment were compared using a randomized controlled design. Forty-four benzodiazepine users seeking in-patient withdrawal treatment at two substance use treatment clinics in Adelaide, Australia were recruited. Measurements included the Severity of Dependence Scale and the SF-36. A scale comprising six items from the Clinical Institute Withdrawal Assessment Scale--Benzodiazepines (CIWA-B) was used to measure withdrawal symptoms. Participants were randomized to receive a fixed diazepam tapering regime or diazepam only in response to withdrawal symptoms (symptom-triggered group). Results showed that there were no significant differences between treatment groups in terms of withdrawal severity, duration of in-patient treatment, amount of diazepam administered, treatment attrition and benzodiazepine use at follow-up. Both groups showed a reduction in benzodiazepine dosage of 86% over the first 8 days which was maintained at 1 month post-discharge. Although there were improvements in some subscales of the SF-36 between baseline and follow-up, values were significantly below age-matched norms at both time-points. This study showed that benzodiazepine users entering treatment have relatively poor health and that symptom-triggered taper methods incorporating flexible dosing and flexible treatment duration are as effective as fixed dose taper methods for in-patient benzodiazepine withdrawal treatment.

Catherine McGregor

Papers

The nature, time course and severity of methamphetamine withdrawal.

Experience of non-fatal overdose among heroin users in Adelaide, Australia: circumstances and risk perceptions

Symptoms and sleep patterns during inpatient treatment of methamphetamine withdrawal: A comparison of mirtazapine and modafinil with treatment as usual

A comparison of antagonist-precipitated withdrawal under anesthesia to standard inpatient withdrawal as a precursor to maintenance naltrexone treatment in heroin users: outcomes at 6 and 12 months.

In-patient benzodiazepine withdrawal: comparison of fixed and symptom-triggered taper methods.