WINDHAM, Maine » Mike Barrett, a corrections officer, ripped open an envelope in the mail room at the Maine Correctional Center and eyed something suspicious: a Father’s Day card, sent a month early. He carefully felt the card and slit it open, looking for a substance that has made mail call here a different experience of late.

Barrett and other prison officials around the country are searching their facilities, mail and visitors for Suboxone, a drug used as a treatment for opiate addiction that has become coveted as contraband. Innovative smugglers have turned crushed Suboxone pills into a paste and spread it under stamps or even over children’s artwork, including pages from a princess coloring book in New Jersey.

The drug also comes in thin strips that dissolve under the tongue, which smugglers have tucked behind envelope seams and stamps.

"It’s become a crisis in here, to be honest with you," said Maj. Francine Breton, administrator of the Cumberland County Jail in Portland, Maine. "It’s the drug of choice right now."

Law enforcement officials say that Suboxone, prescribed to treat addiction to heroin and powerful painkillers like oxycodone, has also become a drug of abuse as its popularity has grown, resulting in prison smuggling efforts from New Mexico to Maine. Addicts buy it on the street when they cannot find or afford their drug of choice, to stave off the sickness that comes with withdrawal. But some are also taking it for the high they say it provides.

After Suboxone strips were discovered in two letters in March, the Cumberland County Jail set a rule that all inmate mail must arrive in white envelopes. That way, Breton said, jail officials can detect the orange tint of the strips when they hold an envelope up to the light.

The jail also rips the stamps off every piece of mail before delivering it to inmates, because senders were putting a paste made of crushed Suboxone pills on the back of stamps for inmates to lick off.

The Maine Correctional Center tightened its mail policy in 2009 specifically because of Suboxone smuggling. Officials there remove all mail from envelopes before delivering it, then send the envelopes to the "burn barrel." Any mail containing crayon scribblings, stickers, glitter glue or any "foreign substance" does not get delivered.

"We’ve had too many people dry the stuff onto the pages, then get a kid to color over it," said Capt. Mark James, who supervises the mail room, adding that Suboxone has at times been discovered on a daily basis.

In Nesquehoning, Pa., officials at the Carbon County Correctional Facility intercepted three letters with Suboxone strips under the stamps in January and later charged five inmates and six others, including the father of one of the inmates, with conspiring to smuggle the drug into the prison.

In Cape May, N.J., three coloring book pages sent to a prisoner in February, including two depicting Snow White and Cinderella, were splotched with the words "To Daddy" and an orange substance that turned out to be Suboxone.

In Massachusetts, Suboxone makes up 12 percent of all contraband discovered in state prisons, according to Terrel Harris, a spokesman for the state’s Department of Public Safety. And in New Mexico, prison officials are foiling attempts to smuggle Suboxone to inmates about once a week, said Shannon McReynolds, a spokesman for the New Mexico Corrections Department.

"Typically what inmates will try to do is quarter the pill up and sell it for $25 a hit," McReynolds said.

The Food and Drug Administration approved Suboxone in 2002 as the first narcotic that doctors could prescribe for addiction to opiates. Seen as a more convenient alternative to methadone, which can be dispensed only at federally licensed clinics, it blocks the effects of opiates while also reducing cravings and easing withdrawal symptoms.

To deter abuse, Suboxone contains naloxone, a substance that precipitates withdrawal symptoms when the drug is injected. Suboxone also has a ceiling effect, with the impact plateauing after a certain dosage.

But users can experience euphoria, especially if they do not take it regularly, and Suboxone is increasingly sold on the street in New England and other regions where it is commonly prescribed.

A Brown University study in 2009 found that only seven state prison systems offered buprenorphine treatment to inmates, and only under narrow circumstances.

The Maine Civil Liberties Union sued last year on behalf of a woman who was arrested on a traffic violation while taking Suboxone for opiate addiction and not allowed to continue treatment in jail. The parties settled out of court, but Zachary Heiden, the group’s legal director, said he would continue to press for Suboxone treatment in the state’s jails.

"If they’re not providing a way for inmates to treat their addictions," he said, "it makes sense that they’re using unlawful means to get that treatment."

Others are probably seeking a high, though some experts interviewed said they were puzzled as to why Suboxone would be more sought after than other opiate drugs.

"Maybe some people think it’s a safer opiate to abuse because of the ceiling effect," said Dr. Daniel P. Alford, a professor at the Boston University School of Medicine who runs a Suboxone clinic at Boston Medical Center.

Or, he added, "Maybe there is some mystique about it."

James described Suboxone as more "adaptable" than other drugs, suggesting it is easier for smugglers to manipulate than other drugs.

William Lawhorn, the director of facility operations for the Vermont Department of Corrections, said Suboxone was the "predominant" contraband in the state’s prisons. Lawhorn said corrections officers have found crushed Suboxone in shoes and the spines of magazines. So many people were sewing Suboxone pills into the seams of clothing and stuffing it into the drawstrings of sweat pants, he said, that one women’s prison would repeatedly wash and dry on high heat every piece of clothing sent in care packages.

At the Maine Correctional Facility one recent morning, Barrett sat at a table in the windowless mail room, slicing open dozens of envelopes. He inspected a photograph and scraped two stamps off a postcard. A card with purple stickers was to be returned to its sender, as was a letter doused in perfume, a technique Barrett said was sometimes used to try to evade drug-sniffing dogs. The week before, he said, a child’s picture tested positive for drugs.

"Every time a drawing comes in from a child, you have to scrutinize it because it might not be from a kid," he said. "It’s sad."

© 2011 The New York Times Company