To address the issue of Fentanyl-related deaths in the United States (US), the US House of Representative Michael McCaul introduced a bill for the Project Precursor Act on 11 May 2023 in the US Congress. The objective of the bill is to disrupt the international fentanyl supply chain. Interestingly, one of the provisions in the bill proposes to amend the Chemical Weapons Convention (CWC) to include each covered fentanyl substance on Schedules 1, 2, or 3 of the Annexure on Chemicals to the CWC. However, amending the CWC is a difficult process, given the current polarised geopolitical scenario. The article looks at the provisions of the Project Precursor bill and explains the procedure to amend the CWC, pointing to the challenges of doing so.