A Beginner's Guide to Glutathione Injections: What to Expect Intramuscular vs Subcutaneous injections what's the difference? At KDR, we often use peptides and wellness injections like NAD, glutathione, and HCG, but they are not all administered the same way. Intramuscular injections ( Why Is Glutathione Added as a Push? Glutathione IV Power How To Give A Subcutaneous Injection And Sites The HCG Institute Subcutaneous Injection: What It Is and How to Give One