The U.S. Food and Drug Administration says drug shortages are possible because of expected long-term power outages in Puerto Rico.
According to the agency, factories in Puerto Rico make nearly 10 percent of the medicines used by Americans, plus numerous medical devices.
FDA Commissioner Dr. Scott Gottlieb said in a statement Friday that the agency is working to prevent shortages of about 40 medicines. He didn't name the medicines involved.
The FDA said it is working with drugmakers, who are trying to restore partial operations with backup generators. In the most urgent cases, the FDA is helping companies get fuel to keep their generators running and ship finished products.
Most of Puerto Rico lost electricity when Hurricane Maria hit the island territory two weeks ago.
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