Guide5 days ago 4 min read
Subcutaneous vs intramuscular: which route, when, and why
Different peptides — and different goals — favor different injection routes.
by Editorial team
Subcutaneous (SC)
SC injections deposit medication into fat tissue under the skin, typically the abdomen or thigh.
Absorption is slower and more even, which suits most peptides intended for systemic effect.
Intramuscular (IM)
IM injections deposit medication into muscle tissue, with faster absorption and higher peak levels.
Used less often for peptides but sometimes preferred for specific compounds.
How to choose
Follow the formulation's recommended route — manufacturers and clinicians base this on pharmacokinetics.
If unsure, default to the clinically prescribed route and do not switch on your own.