Tyler's Law directs the Secretary of Health and Human Services to study and provide guidance on whether hospitals should routinely test overdose patients for fentanyl in emergency departments. The Secretary must complete the study within one year, examining how often emergency departments currently test for fentanyl, the associated costs, potential benefits and risks for patients, and how such testing might affect patient privacy and the doctor-patient relationship. Within six months after the study concludes, the Secretary must issue guidance addressing whether fentanyl testing should become standard practice, how to ensure emergency department staff know which substances their drug tests screen for, and how fentanyl testing might affect future overdose risk and overall health outcomes. The bill applies to all hospital emergency departments nationwide and was introduced by Senators Joe Manchin and Mike Braun in December 2023. No specific funding amount is allocated in the legislation.