The FDA said the medicine has been used for many years to relieve acute and chronic pain, but the new concentration of morphine -- 100 milligrams per 5 milliliters or 20 milligrams per 1 milliliter -- had not been FDA-approved until now.
The action is part of the FDA's unapproved drugs initiative, designed to make sure marketed drugs meet current FDA standards.
The morphine sulfate oral solution is manufactured by Roxane Laboratories of Columbus, Ohio.
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