Thirty-two states now require the National Precursor Log Exchange (NPLEx) to be used for every pseudoephedrine and ephedrine OTC purchase, and ten of the eleven largest pharmacy chains in the US voluntarily contribute all of their similar transactions to NPLEx. These states have seen dramatic results in reducing the number of methamphetamine laboratory seizures. Prior to implementation of the system in Tennessee in 2005, methamphetamine laboratory seizures totaled 1,497 in 2004, but were reduced to 955 in 2005, and 589 in 2009. Kentuckys program was implemented statewide in 2008, and since statewide implementation, the number of laboratory seizures has significantly decreased. Oklahoma initially experienced success with their tracking system after implementation in 2006, as the number of seizures dropped in that year and again in 2007. In 2008, however, seizures began rising again, and have continued to rise in 2009. Nonetheless, when Oklahoma adopted NPLEx, their lab seizures also dropped significantly. NPLEx appears to be successful by requiring the real-time submission of transactions, thereby enabling the relevant laws to be enforced at the point of sale. By creating a multi-state database and the ability to compare all transactions quickly, NPLEx enables pharmacies to deny purchases that would be illegal based on gram limits, age, or even to convicted meth offenders in some states. NPLEx also enforces the federal gram limits across state lines, which was impossible with state-operated systems. Access to the records is by law enforcement agencies only, through an online secure portal.
In popular culture
In the pilot episode of Breaking Bad, Walter White first synthesizes methamphetamine through the Nagai route, using  red phosphorus and iodine to reduce pseudoephedrine. In the episode "Vitamin D" of Glee, Terri takes a job as the school nurse to stop her husband, Will Schuester, from becoming closer to guidance counsellor Emma Pillsbury (Jayma Mays), but is fired after giving the students performance-enhancing pseudoephedrine tablets. In her 2013 single "Avant Gardener", Australian rock musician Courtney Barnett refers to the effects of pseudoephedrine: "Reminds me of the time / When I was really sick and I / Had too much pseudoephedrine and I / Couldnt sleep at night". In her 2017 album Melodrama, pop artist Lorde references pseudoephedrine on the song "Writer in the Dark". The lyric reads: "I still feel you, now and then / Slow like pseudoephedrine / When you see me, will you say Ive changed?" Synthesis
Although pseudoephedrine occurs naturally as an alkaloid in certain plant species (for example, as a constituent of extracts from the Ephedra species, also known as ma huang, in which it occurs together with other isomers of ephedrine), the majority of pseudoephedrine produced for commercial use is derived from yeast fermentation of dextrose in the presence of benzaldehyde. In this process, specialized strains of yeast (typically a variety of Candida utilis or Saccharomyces cerevisiae) are added to large vats containing water, dextrose and the enzyme pyruvate decarboxylase (such as found in beets and other plants).