After the final approval on Friday, Dr. Scott Gottlieb, the F.D.A. commissioner, released a lengthy statement defending the agency’s decision. He emphasized that Dsuvia is delivered through a “pre-filled, single-dose applicator,” and said that its only permitted use will be in hospitals, surgical centers and other medically supervised settings. It is ideally suited for certain special circumstances, he said, particularly for soldiers wounded on the battlefield who might not have access to intravenous painkillers.

Dr. Gottlieb wrote that Dsuvia will not be dispensed to patients for home use or available at retail pharmacies, and that it should only be administered by health care providers with the single-dose applicators. It will likely hit the market early next year.

“These measures to restrict the use of this product only within a supervised health care setting, and not for home use, are important steps to help prevent misuse and abuse,” he wrote.

He also pointed to the agency’s new powers to require post-market studies evaluating the efficacy of opioid medications that the F.D.A. might be having second thoughts about, and to consider abuse risk as a factor in making regulatory decisions about drugs after, as well as before, they’re on the market. Last year, the F.D.A. asked the maker of Opana ER, another super-potent opioid, to take it off the market because of concerns about abuse.

Vince Angotti, the chief executive of AcelRx, said in a statement that the company would diligently follow a safety program, known as a risk evaluation and mitigation strategy, that the F.D.A. had approved for Dsuvia, including monitoring distribution of the drug and auditing wholesalers’ data; evaluating whether hospitals and other health care providers are using the drug properly; and monitoring for any diversion or abuse.