This bill amends the federal drug discount program, known as the 340B program, to allow rural emergency hospitals to participate and receive discounted pharmaceutical prices. Currently, the 340B program provides discounts on medications for certain healthcare entities that serve vulnerable populations, but rural emergency hospitals have been excluded from this benefit. The legislation expands eligibility to include rural emergency hospitals that are government-owned, nonprofit organizations with government powers, or private nonprofits with contracts to serve low-income and uninsured patients. The bill includes a transition rule stating that only rural emergency hospitals that were already participating in the program before the bill's enactment can continue to do so, preventing new entities from gaining access retroactively. This change is intended to help rural hospitals reduce their drug costs and improve their ability to serve communities in underserved areas.