The Food and Drug Administration says it has approved the first generic versions of the blockbuster antidepressant drug Cymbalta, offering lower-cost access to one of the most widely prescribed treatments for depression, anxiety and other disorders.

Cymbalta is Eli Lilly & Co. Inc.'s best-selling drug and posted 2012 sales of $4.7 billion, making it the fifth-highest selling medication worldwide. The drug's patent expired Thursday, clearing the way for the launch of cheaper versions of the drug from generic drugmakers.

Besides depression, Cymbalta is also prescribed to treat generalized anxiety disorder, diabetic nerve pain, fibromyalgia and forms of chronic pain.

The FDA said it approved six of the pill from generic drugmakers including Dr. Reddy's Laboratories Ltd., Sun Pharma Global and Teva Pharmaceuticals.