Hydrocodone is the most prescribed drug in the United States. Now the Food and Drug Administration (FDA) is recommending restrictions on medicines that contain the drug.

The FDA said that it will make a formal request to have hydrocodone reclassified as a Schedule II drug in December. If this passes, medical professionals will be limited in the number of hydrocodone prescriptions they can write, and refills will be limited to a 90-day supply. In addition, physician assistants and nurses will not be qualified to write the prescriptions.

According to an online notice that the FDA posted on Thursday, the drug should be as restricted as other narcotics like morphine or oxycodone.

Hydrocodone has been able to slide pass strict regulations because it is only ever available combined with non-addictive ingredients like acetaminophen or aspirin. As a result, the drug became health care professionals' number one drug prescribed for chronic pain issues like toothaches, arthritis and back pain, Associated Press reports.

Hydrocodone can be found in Vicodin and its generic versions. It is considered an opioid, a classification of drugs that include codeine, methadone and heroin. In 2011, doctors wrote over 131 million prescriptions for hydrocodone. Every year, the Drug Enforcement Administration (DEA) ranks hydrocodone and oxycodone as either the first or second most-abused medicine in the United States.

"The FDA has become increasingly concerned about the abuse and misuse of opioid products, which have sadly reached epidemic proportions in certain parts of the United States," Dr. Janet Woodcock, American Medical Association's top drug regulator, said in a statement on Thursday,

More than a decade ago, the DEA asked the FDA to re-classify hydrocodone into the same category as other addictive painkillers. The FDA, however, never made a formal announcement about the request.

Hydrocodone has been a Schedule III drug since 1970. As a result, medicines with the drug can be refilled five times before patients have to get a new prescription.

"So you have to consider the secondary, unintended consequences: patients who are legitimate users who may lose access, or be restricted," Edward Michna, assistant professor at Harvard Medical School told Bloomberg. "It's all a balance."

It is up to the officials from various agencies in the Department of Health and Human Services to approve the reclassification.

"The FDA's reported decision will likely pose significant hardships for many patients and delay relief for vulnerable patients with legitimate chronic pain, especially those in nursing home and long-term care," Kevin Schweers, a spokesman for the National Community Pharmacists Association, said.

Related