When Indiana restricted the sale of over-the counter cold medicines (search) this year, pharmacist Dan Beyer suddenly found himself a front-line defender in the state's war against methamphetamine (search).

But meth producers sidestepped the battle by stockpiling supplies in states that don't limit sales of pseudoephedrine (search), a popular ingredient in the highly addictive stimulant.

"They're going to the places with the least resistance," said Beyer, who owns the Rising Sun Pharmacy, about 90 miles southeast of Indianapolis and just 15 miles from Ohio, which does not restrict pseudoephedrine sales.

"If we're going to do all this work and all they have to do is cross a river, we've accomplished absolutely nothing," he said.

It's an increasingly common dilemma because of the patchwork of laws aimed at controlling methamphetamine.

Thirty-seven states restrict sales of pseudoephedrine, a key ingredient in at least a dozen cold medicines. But the laws vary from requiring a prescription to simply limiting the number of packages purchased at the same time.

Thirteen states, including New York and South Carolina, have no pseudoephedrine laws, according to the National Conference of State Legislatures. At least two of those — Massachusetts and Ohio — have legislation pending.

Law officers say meth producers have exploited these differences by crossing state lines in search of ingredients or by "pharmacy shopping" in states that require a log of purchases but lack the means to cross-reference entries.

"What we're beginning to see is people traveling great distances to get pseudoephedrine," said Jack Riley, assistant special agent in charge of the U.S. Drug Enforcement Administration in St. Louis.

That has undermined anti-meth efforts in states such as Oregon.

The state, which had 447 meth labs in 2004, has begun requiring a prescription to buy products containing pseudoephedrine. But two of its neighbors — Idaho and California — have looser restrictions, and one — Nevada — has none.

"There is always some concern meth cooks can get to pseudoephedrine," said Oregon State Police Capt. Ed Mouery, who was on the state's Methamphetamine Task Force.

States without pseudoephedrine laws acknowledge meth is a problem, but some say tight budgets have reduced support for restrictions. Others are struggling with how to restrict a legitimate product.

"Pseudoephedrine helps people with sinus conditions," said Ohio state Sen. John Carey, a Republican who sponsored a bill that would limit purchases to 9 grams in 30 days and require stores to collect names and signatures for all purchases. "We don't want to keep people from buying it, we just want to restrict how much they can get to make meth."

Keith Cain, sheriff of Daviess County in western Kentucky, said a unified effort is key to stopping meth production. His department found 62 meth labs last year and had 159 meth-related indictments in 2003, the most in the state.

"This shouldn't be viewed as a panacea that's going to rid our communities of meth," he said of pseudoephedrine controls. "It's a very complex issue, and it's going to take a very complex solution."

Some on Capitol Hill are listening. Last month, the U.S. Senate approved a bipartisan bill that would provide federal controls to fight meth, which comes in the form of a crystal-like powder or rocklike chunks and can be smoked, snorted, injected or swallowed.

Consumers would have to show a photo ID, sign a log and receive no more than 7.5 grams — or about 250 30-milligram pills — in a 30-day period. Computer tracking would prevent customers from exceeding the limit at other stores.

The bill is headed for a conference committee.

"We need to be careful that we don't push the problem around from one weakest state to the next," said Dave Murray, a White House policy analyst with the Office of National Drug Control Policy. "You've got to craft a solution that preserves security and still provides access to the medicines that millions of Americans need."

Eric Lawrence, director of forensic analysis for the Indiana State Police, believes a federal law would help.

The number of methamphetamine labs seized in Indiana rose nearly 800 percent — from 177 to 1,549 — between 1999 and 2004, police said. The surge has strained local budgets, crowded jails and increased the number of children needing services as a result of meth abuse in the home.

Indiana has seen a glimmer of hope since its law took effect July 1. The law limits consumers to 3 grams of pseudoephedrine over seven days or 9 grams in a month. Pharmacies are required to see identification, keep the drug behind counters and maintain a log of purchases.

The number of meth-lab busts in Indiana fell from 153 in July and August last year to 113 during the same period in 2005, the first two months under the new law.

"The bottom line is that if they can't get pseudoephedrine, they can't make meth," Lawrence said. "If you could take this product away from people overnight, tomorrow morning you'd wake up and there would be no meth labs."