Consumers will soon face further restrictions when buying cold medicine that contains pseudoephedrine as Hawai'i follows a national effort to limit an ingredient that can be used to make crystal methamphetamine, or ice.

Lt. Gov. James "Duke" Aiona signed a bill into law yesterday that limits consumers without a prescription to 3.6 grams — or about one package — of medicine with pseudoephedrine a day and 9 grams — or three packages — a month. Consumers also will have to show identification and sign a log that may be examined by law enforcement in drug investigations.

Retailers will be required to put pseudoephedrine products behind the counter or in locked display cases. The new law, which mirrors federal pseudoephedrine controls added to the USA Patriot Act this year, will take effect in October.

The state passed a law in 2005 that limited consumer purchases of pseudoephedrine products to 9 grams at one time. But the state Legislature agreed to revise the law after the federal changes in the Patriot Act.

"This law works. It cuts the supply tremendously. And it's something that we sorely needed in this state," Aiona said at a news conference at the state Capitol with U.S. Attorney Ed Kubo, Honolulu Prosecutor Peter Carlisle and other federal and state law enforcement officials.

Most of the ice in Hawai'i is smuggled in by drug traffickers, not produced using pseudoephedrine at local laboratories, so the impact of the new law on the drug trade may not be immediate. Keith Kamita, chief of the narcotics enforcement division at the state Department of Public Safety, said the state documented 17 meth labs last year and one so far this year.

Kamita said the new law might deter drug dealers from turning to homemade labs if the cost of smuggled ice increases or if the supply declines.

"We will see a big reduction in laboratories," he said.

Law enforcement also will develop a tracking system to catch people who go from store to store, or from island to island, to try to evade the restrictions and stockpile pseudoephedrine.

Many retailers already have voluntarily moved pseudoephedrine products behind the counter, and some have started asking customers for identification.

Carol Pregill, president of the Retail Merchants of Hawai'i, said she has not heard any complaints from retailers but believes some consumers will not like going through the extra trouble.

"It's additional work, certainly," Pregill said. "But it's a greater inconvenience for customers."

Some state lawmakers have been critical of Aiona and the Lingle administration for a lack of focus on ice, which was described a few years ago as the state's biggest narcotics problem. Aiona has been using a broader strategy that includes warnings to young people about underage drinking and drug abuse.

"If we don't take care of business from the beginning, in other words, from our young keiki, our young people, and change that attitude that we now have in regards to drugs and alcohol, we're going to be battling this like we've been battling it for the last generations before us," Aiona said.

Aiona signed the bill yesterday as acting governor because Lingle was in Washington, D.C.

Reach Derrick DePledge at ddepledge@honoluluadvertiser.com.