Rifampin for Injection, USP, 600 mg/vial, Rx only, Manufactured for: Mylan Institutional LLC, Rockford, IL 61103; NDC 67457-445-60.
Failed Impurities/Degradation Specifications: discoloration due to elevated unknown impurity results which could decrease the effectiveness of the product.
Nationwide in the USA
https://www.accessdata.fda.gov/scripts/ires/index.cfm?Product=D-0139-2020