U.S. senator launches probe into five top opioid drugmakers

(Reuters) - U.S. Democratic Senator Claire McCaskill sought on Tuesday details from the nation's top opioid drugmakers on their sales and marketing practices, as lawmakers step up efforts to tackle the country's deadly opioid crisis.The Missouri senator's investigation comes amid an epidemic of opioid addiction, with 91 Americans dying everyday as a result of overdose, according to the U.S. Centers for Disease Control and Prevention."This epidemic is the direct result of a calculated sales and m