The Food and Drug Administration has laid out a roadmap for greater strictures on the prescribing and dispensing of hydrocodone and analgesics that contain it. The move is the latest in a chain of actions taken by the FDA and other agencies to address a burgeoning U.S. crisis of addiction to opioid painkillers.

Under a plan announced by the FDA on Thursday afternoon, products containing the opioid painkiller hydrocodone, including combination analgesics such as Vicodin (which mixes hydrocodone with acetaminophen) will be classified by the Drug Enforcement Agency as Schedule II substances, with added restrictions in who may prescribe them and how they may be dispensed by pharmacies.

Here's a list of the marketed products that contain hydrocodone.

Schedule II drugs are defined as drugs "with a high potential for abuse." Medications and combination products containing fewer than 15 mg of hydrocodone per dose are currently considered Schedule III products, a classification assigned to drugs considered to have "moderate to low potential for physical and psychological dependence."

The proposed rescheduling could usher in significant changes for patients prescribed painkillers by their healthcare provider. Schedule III prescriptions (such products' current designation) may be refilled as many as five times in six months; Schedule II prescriptions may not be refilled without a newly-written prescription. Unless it's an emergency situation, a physician issuing a prescription for a Schedule II substance may not call such a prescription into a pharmacy by phone; in an emergency, the physician must send a written prescription to the dispensing pharmacy within seven days. And a pharmacist is not permitted to change the strength, dosage, formulation or quantity prescribed of a Schedule II product, nor to change the address of the consumer receiving the prescription.

The FDA recommendations come in response to a 2009 request by the Drug Enforcement Administration to consider whether further restrictions on opioid prescribing would be appropriate. The FDA's recommendations now go to the Department of Health and Human Services, and then to the DEA, before a final determination is made. The National Institute on Drug Abuse is expected to weigh in positively on the proposal.

In 2010, more than 12 million Americans reported abusing prescription painkillers, and emergency room visits for overdose of opioid medications doubled in the five years leading up to 2009, when 475,000 such visits were attributed to the medications. In 2008, opioids were the cause of close to 15,000 overdose deaths in the United States.