“The illicit production of methamphetamine [a highly addictive stimulant drug] from the precursor pseudoephedrine in clandestine laboratories fuels up to 35 percent of the domestic supply. Public health, law enforcement, and medical associations support restricted access to methamphetamine precursors; manufacturers oppose restrictions,” writes Jeffery Talbert, Ph.D., of the University of Kentucky College of Pharmacy, Lexington, and colleagues. Kentucky law limits pseudoephedrine sales in all counties to 7.2 grams/person/month (as of July 2012, formerly 9 grams/person/month), sufficient to allow a patient to take the maximum daily dose (240 mg/d) each day. Electronic tracking of sales is also required. Despite these restrictions, increases in the number of reported methamphetamine laboratory seizures (called laboratories) continue.
As reported in a Research Letter, the authors analyzed the relationship between pseudoephedrine sales and the number of laboratories reported in Kentucky using county level data from 2010. Law enforcement regulations define laboratories as "requiring two or more chemicals or two or more pieces of equipment used in manufacturing methamphetamine.” The authors found that in 2010, Kentuckians purchased an average of 24,664 g of pseudoephedrine per county and 1,072 laboratories were reported. There was considerable variability in pseudoephedrine sales per county. Counties with greater pseudoephedrine sales were significantly associated with having greater numbers of laboratories. “The strength of this study is that it is the first, to our knowledge, to provide empirical evidence that pseudoephedrine sales are correlated with the clandestine manufacture of methamphetamine,” the researchers write. “… this study highlights the need for research on various approaches to containing clandestine methamphetamine production, including restriction of pseudoephedrine sales to only those patients who have a true medical need for its decongestant properties.”