The federal government has placed new restrictions on the prescribing of medications containing the opioid hydrocodone.

Effective Oct. 6, the U.S. Drug Enforcement Agency (DEA) has published a final rule reclassifying hydrocodone combination products (HCPs), defined as medications combining hydrocodone and another drug, from Schedule III to the more restrictive Schedule II. The proposed rule follows the recommendation of a Food and Drug Administration (FDA) Public Advisory Committee meeting held in January last year. The FDA  also cited its duty to protect the health and safety of the public as a motivating factor. The change comes after months of public comment and a physician’s petition originally submitted in 1999, according to the DEA.

“Almost seven million Americans abuse controlled-substance prescription medications, including opioid painkillers, resulting in more deaths from prescription drug overdoses than auto accidents,” DEA Administrator Michele Leonhart said in a news release. “[The rule change] recognizes that these products are some of the most addictive and potentially dangerous prescription medications available.”

The change means patients taking HCP painkillers like Vicodin, Lortab or Norco will be limited to an initial 90-day supply and then will have to call or visit their doctor for a new prescription each time they need a refill. Although the Controlled Substances Act prohibits refills of prescriptions for Schedule II controlled substances, a practitioner may issue multiple Schedule II prescriptions in order to provide up to a 90-day supply of medication.

Additionally, the new rule means patients generally must provide a written prescription to a pharmacist to receive the drug. In most instances, prescribers will no longer be able to call in a new prescription or a refill, unless criteria for an emergency situation are met.

Notably, DEA stated in its final rule that prescriptions for HCPs issued before October 6 with legitimate refills may be dispensed before April 8, 2015, however some pharmacies may not be refilling them due to software issues and confusion around conflicting state laws.

Hydrocodone, metabolized by the body’s highly genetically variable CYP2D6 enzyme, is an ingredient in dozens of combination medications, from painkillers to cough suppressants.  The American Academy of Family Physicians (AAFP) reports that HCPs are the most prescribed medications in the U.S., with 135 million prescriptions filled in 2012.

The DEA had been accepting public input on the change since February and had received nearly 600 comments. NationalPainReport.com writes that more than half of the comments (52 percent) supported the rescheduling while 41 percent opposed it.

Multiple news sources have reported concern from pain management experts over the rule change, citing fears that patients may have more difficulty getting medications they rely upon. In a comment letter to the DEA, the American Academy of Pain Medicine (AAPM) wrote that the schedule change may be beneficial in that it might encourage doctors to look more critically at their prescribing practices.

“On the other hand,” the AAPM letter says, “current patients with legitimate medical need may have problems obtaining their medication, particularly if they live in rural or other underserved areas. Their costs may increase through more co-pays, more clinic visits, and the higher price of a Schedule II medication.”

More details on the new DEA rule can be found here. The AAFP has also produced a helpful guide to how the rescheduling affects physicians and their patients.