Department of Family and Community Medicine, The University of Arizona, Tucson, AZ, USA.
Drug Alcohol Depend. 2012 Nov 1;126(1-2):55-64. doi: 10.1016/j.drugalcdep.2012.04.011. Epub 2012 May 15.
Clandestine laboratory operators commonly extract ephedrine and pseudoephedrine-precursor chemicals used to synthesize methamphetamine-from over-the-counter cold/allergy/sinus products. To prevent this activity, two states, Oregon in 07/2006 and Mississippi in 07/2010, implemented regulations classifying ephedrine and pseudoephedrine as Schedule III substances, making products containing them available by prescription only. Using simple pre-regulation versus post-regulation comparisons, reports claim that the regulations have substantially reduced clandestine laboratory seizures (an indicator of laboratory prevalence) in both states, motivating efforts to implement similar regulation nationally. This study uses ARIMA-intervention time-series analysis to more rigorously evaluate the regulations' impacts on laboratory seizures.
Monthly counts of methamphetamine clandestine laboratory seizures were extracted from the Clandestine Laboratory Seizure System (2000-early 2011) for Oregon, Mississippi and selected nearby states (for quasi-control).
Seizures in Oregon and nearby western states largely bottomed out months before Oregon's regulation, and changed little thereafter. No significant impact for Oregon's regulation was found. Mississippi and nearby states generally had elevated seizures before Mississippi's regulation. Mississippi experienced a regulation-associated drop of 28.9 seizures (50.2%) in the series level (p<0.01), while nearby states exhibited no comparable decline.
Oregon's regulation encountered a floor effect, making any sizable impact infeasible. Mississippi, however, realized a substantial impact, suggesting that laboratories, if sufficiently extant, can be meaningfully impacted by prescription precursor regulation. It follows that national prescription precursor regulation would have little impact in western states with low indicated laboratory prevalence, but may be of significant use in regions facing higher indicated prevalence.
秘密实验室操作人员通常从非处方感冒/过敏/鼻窦产品中提取麻黄素和伪麻黄素前体化学物质，用于合成甲基苯丙胺。为了防止这种活动，俄勒冈州于 2006 年 7 月和密西西比州于 2010 年 7 月实施了法规，将麻黄素和伪麻黄素列为附表 III 物质，使含有这些物质的产品只能凭处方购买。使用简单的监管前后比较，报告声称这些法规大大减少了这两个州的秘密实验室缉获量（实验室流行率的一个指标），促使人们努力在全国范围内实施类似的监管。本研究使用 ARIMA 干预时间序列分析更严格地评估法规对实验室缉获量的影响。
从秘密实验室缉获系统（2000 年至 2011 年初）中提取俄勒冈州、密西西比州和选定的附近州（准对照）的甲基苯丙胺秘密实验室缉获的月度计数。
俄勒冈州和附近的西部各州的缉获量在俄勒冈州法规出台前几个月大幅见底，此后变化不大。未发现俄勒冈州法规有显著影响。密西西比州和附近各州在密西西比州法规出台前缉获量普遍较高。密西西比州在该系列中经历了 28.9 次缉获（50.2%）的监管相关下降（p<0.01），而附近各州则没有类似的下降。
俄勒冈州的法规遭遇了下限效应，使得任何大规模的影响都不可行。然而，密西西比州实现了显著的影响，这表明如果实验室存在足够数量，处方前体法规可以对其产生有意义的影响。因此，在实验室流行率低的西部各州，全国性的处方前体法规几乎没有影响，但在面临较高实验室流行率的地区可能具有重要意义。
