LONDON, Ky. -- Law enforcement agencies are increasingly relying on computerized tracking systems in their fight against methamphetamine, an illegal drug that is often brewed in makeshift labs and has become a particular scourge in Appalachia and the Midwest, following decades of plaguing the West Coast.

Tracking systems are being installed gradually in pharmacies nationwide in response to a federal law that, since March 2006, has regulated purchases of pseudoephedrine, a key ingredient in the manufacture of meth. Pseudoephedrine is found in many over-the-counter cold and allergy medicines, such as Sudafed.

Under federal law, customers must show photo ID to buy pseudoephedrine, and the legal limit for purchases is 9 grams per month -- roughly the equivalent of two 15-dose boxes of 24-hour Claritin D, or three 10-dose boxes of Aleve Cold & Sinus, or six 24-dose boxes of Sudafed.

Limiting purchases of pseudoephedrine prevents meth producers from buying the chemical in bulk at any one store, and a computerized tracking system prevents the producers from exceeding the limit by going to one pharmacy after another.

Not yet here

But while all stores in the nation now must ask consumers to give their name when buying pseudoephedrine, California and most other states do not yet have a system for tracking purchases from store to store, said Tony Loya, national coordinator of the Meth and Chemicals Initiative in the San Diego office of the National Drug Control Policy.

"We're working on the problem and someday we'll be able to look at it immediately," Loya said about the consumer information collected in stores.

Until such a system is in place, there is no single way for a pharmacy to immediately know whether a customer has already made the maximum-allowed purchase at another store, he said.

Loya said Tennessee has what is considered a national model for computerized tracking of pseudoephedrine products. A proposed congressional bill would provide funding for all states to adopt a computerized system, Loya said.

Tracking systems such as the one in use in Kentucky, MethCheck, automatically collect the buyer's name, address and age with a swipe of a driver's license or state-issued identification card.

Shopping trips

Then the system notifies detectives via e-mail when a customer has exceeded the purchase limit. It also allows law enforcement to quickly spot suspicious patterns -- for example, someone who might be trying to skirt the purchase limits by going from pharmacy to pharmacy and buying a few packages at a time.

Case in point:

Detective Brian Lewis returned to his desk after lunch, scanning e-mails he missed.

One caught his eye. It said a suspected member of a methamphetamine ring bought a box of Sudafed at 1:34 p.m. at a CVS pharmacy.

Minutes later, Lewis was in his truck, circling the parking lot, searching for the woman.

Lewis did not find her that day, but the scenario illustrated the way the tracking system was set up to work.

An updated version of MethCheck eventually will enable law enforcement to track purchases by neighborhood or street.

That could help detectives spot instances in which a meth chemist enlists others in the neighborhood to buy pseudoephedrine for him, Lewis said.

In addition, the system can flag purchases by people already under suspicion among authorities.

Trail blazing

Kentucky is the first state to use MethCheck; it has been testing it in Laurel County since mid-2005. MethCheck will be used at some 7,000 pharmacies in 43 states by 2008, said Rick Jones, spokesman for Louisville-based Appriss Inc., which developed MethCheck.

Lewis, who heads the MethCheck initiative at Operation UNITE, a federally funded drug task force in Kentucky, said he has used the system to build cases against dozens of people.

Consumer privacy watchdogs are troubled by the technology, worrying that people with colds or allergies could come under suspicion for unwittingly exceeding the purchasing limits by stocking up for themselves or family members. That has happened to at least eight people in Kentucky, according to Lewis.

"People's health information -- it's intimate, it's personal, it's something people desperately want to keep private," said Beth Wilson, executive director of the American Civil Liberties Union in Kentucky. "For law enforcement to do an investigation, there must be a reasonable suspicion. I'm not sure just the amount of medication justifies that."

Not the last word

Authorities said evidence from MethCheck leads only to preliminary interviews with police and is not enough to warrant an arrest.

"It's just an investigative tool," said Van Ingram of the Kentucky Office of Drug Control Policy. "During the course of any investigation, you're sometimes going to interview people who aren't guilty of wrongdoing but who are part of the investigative process."

CVS, the nation's largest pharmacy chain, is participating in the voluntary Kentucky program and plans to install MethCheck in most of its 6,200 stores across the nation by the fall.

"We wanted to make sure we were in compliance (with federal law) and have a solution that would be the least time-consuming for our customers and easiest for employees," CVS spokesman Mike DeAngelis said

Arkansas started testing another program, Leads on Labs, in North Little Rock pharmacies last year.

The nation's largest retailer, Wal-Mart, said it is working to develop its own tracking system.

In Kentucky, the goal is to have some sort of electronic tracking in all of the state's 1,290 pharmacies by the fall, at a cost estimated at up to $500,000.

Under state law, pharmacies must employ electronic tracking if the state foots the bill.

Drugstore customers "put up a little bit of a fuss," said Amanda Hall, a pharmacy technician at a Kroger supermarket in London. "It's usually the legitimate ones who think they're being picked out of a crowd, but they're not."