July 16 (HealthDay News) -- The potent opioid medication Onsolis (fentanyl buccal soluble film) has been approved by the U.S. Food and Drug Administration to treat breakthrough cancer pain, the agency said Thursday.

Onsolis delivers the medication fentanyl through an absorbable film that adheres to the inside of the user's cheek, according to an FDA news release. It's been sanctioned for people 18 and older who already use round-the-clock opioid medication to manage pain. Breakthrough pain occurs when severe flares of pain prove inadequate for daily pain medication.

Onsolis is subject to abuse, and was approved under the agency's Risk Evaluation and Mitigation Strategy program, which requires the drug's maker to submit a plan for managing its risks. Under a companion program, only registered prescribers and pharmacies will be able to dispense the drug, and only registered users will be able to receive Onsolis, the FDA said.

The drug was approved with the agency's most serious "black-box" label warning, stating that the medication is not meant to remedy pain from migraines, dental problems or procedures, or post-operative pain. The labeling also warns that the drug should be kept out of the reach of children.

Onsolis is manufactured by Aveva Drug Delivery Systems of Miramar, Fla.