A drug used to treat depression and peripheral neuropathy (pain, numbness, tingling, burning, or weakness in the hands or feet) that can occur with diabetes. It is also being studied in the treatment of peripheral neuropathy caused by certain anticancer drugs. Cymbalta increases the amount of certain chemicals in the brain that help relieve depression and pain. It is a type of serotonin and norepinephrine reuptake inhibitor. Also called duloxetine and duloxetine hydrochloride.