The U.S. has addressed the opioid crisis using a two-front approach: state regulations limiting opioid prescriptions for acute pain patients, and voluntary federal CDC guidelines on shifting chronic pain patients to lower opioid doses and non-opioids. No opioid policy research to date has accounted for this two-pronged approach in their research design. We develop a theory of physician prescribing behavior under this two-pronged incentive structure. Using the Medical Expenditure Panel Survey, we empirically corroborate the theory: regulations and guidelines have the intended effects of reducing opioid prescriptions for acute and chronic pain, respectively, as well as the predicted unintended effects—income effects cause regulations on acute pain treatment to increase chronic pain opioid prescriptions and the chronic pain treatment guidelines spillover to reduce opioids for acute pain. Moreover, we find that the guidelines worked as intended in terms of the reduced usage, with chronic pain patients shifting to non-opioids and also tapering opioid doses. For those who discontinued opioids under regulations and guidelines, we find no harm in terms of increased work limitations due to pain a year after discontinuing opioids. Finally, we observe an unexplained dichotomy—regulations reduce opioid use by causing fewer new starts, whereas guidelines reduce opioid use by discontinuing current users, with no impact on new starts.