The Centers for Disease Control and Prevention will accept comments through Jan. 13 on draft guidelines for primary care physicians prescribing opioids to adults for chronic pain in outpatient settings. The voluntary guidelines summarize scientific knowledge about the effectiveness and risks of long-term opioid therapy, and provide recommendations for when to initiate or continue opioids for chronic pain; opioid selection, dosage, duration, follow-up and discontinuation; and assessing risk and addressing harms of opioid use. They would not apply to active cancer treatment, palliative care or end-of-life care.