When sourcing injectable Glutathione, it is critical to ensure the manufacturer adheres to GMP (Good Manufacturing Practice) standards. You must verify that the product has a COA (Certificate of Analysis) for every batch, confirming the purity levels (typically >99%) and the absence of heavy metals or microbial contaminants. For international trade, look for suppliers with ISO 13485 or CE certification, and ensure the product is registered with the relevant Ministry of Health or FDA in the destination country.