This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Medicine
First line drug used for painful diabetic neuropathy is ? 
Select and explain. 
A. Carbamazepine, B. Duloxetine, C. Venlafaxine, D. EMLA
B: Duloxetine
Answer: B: Duloxetine 
Explanation: Chronic, painful diabetic neuropathy is difficult to treat but may respond to duloxetine, amitriptyline, gabapentin, valproate, pre- gabalin, or opioids. Two agents, duloxetine and pregabalin, have been approved by the U.S. Food and Drug Administration (FDA) for pain associated with diabetic neuropathy, but no treatments are satisfactory. Reference : page 2427 Harrison's Principles of Internal Medicine 19th edition