FDA highlights concerns with using dietary ingredient glutathione to compound sterile injectables FDA Injectable Glutathione Which Area of the Body Is Best to Inject Glutathione? Glutathione Strive Pharmacy Injection sites vary by type (subcutaneous SQ or intramuscular IM), with common SQ areas including the abdomen (away from navel), thighs, and upper arms, while IM sites are typically the deltoid, Glutathione IM Shots: Advanced Antioxidant & Immune Support: Irina Gressel, MD: Family Medicine