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Some Americans suffering from chronic pain have recently lost access to medicines that helped them live normal lives. Other patients have had to turn to invasive and dangerous treatments, like spinal injections.

“Consequently, patients have endured not only unnecessary suffering, but some have turned to suicide or illicit substance use,” more than 300 medical experts, including three former White House drug czars, wrote in a letter this month. “Others have experienced preventable hospitalizations or medical deterioration.” The experts sent the letter to the Centers for Disease Control and Prevention, urging officials there to take action.

What’s going on? The C.D.C.’s crackdown on the overuse of opioids — though overdue and necessary — is also too uniform. It has ignored the fact that many people receive huge benefits from opioids and use them safely. The crackdown, which began with new guidelines for doctors issued in 2016, is denying medications to people who need them.