The Pew Charitable Trusts

State and federal law enforcers already have their hands full trying to fight the use of methamphetamine, the highly addictive street drug that has wreaked havoc from Oregon to Maine. Now, other meth-like substances — which can produce a similarly dangerous and potentially violent high in those who take them — are prompting new concerns from government officials.

The substances are white, crystallized powders that are sold legally online and in many convenience stores and gas stations around the country as "bath salts." Like meth or cocaine, the powders can be snorted or smoked, and are often marketed under names including "Ivory Wave," "White Rush" or "Vanilla Sky."

The products are attracting scrutiny at every level, from the White House to local police departments. Gil Kerlikowski, the nation's drug czar, warned last week that the powders can "pose a serious threat to the health and well-being of young people and anyone who uses them," according to The Associated Press . At the state level, Florida recently joined Louisiana in banning their sale, reports National Public Radio .

The effects of abusing so-called "bath salts" can be dramatic, sources tell NPR.  Those who take them can experience a kind of "psychotic break," in the words of Mark Ryan, director of the Louisiana Poison Center. "They're extremely anxious and combative, they think there's stuff trying to get them, they're paranoid, they're having hallucinations. So, the encounters are not pleasant."

In Michigan, emergency departments have reported 18 cases involving "bath salts" in recent weeks, The Grand Rapids Press reports . "It certainly is nasty stuff," a spokeswoman for the state community health department says. "It is something that has spread very quickly across the country."