What is subcutaneous administration?

Subcutaneous administration means delivery into the layer of fat between the skin and the muscle beneath it — often abbreviated subq, sub-Q or SC.

Why the route is chosen

Subcutaneous tissue is less vascular than muscle. That produces slower, more sustained absorption, which suits compounds intended to maintain a level rather than spike. It also accommodates only small volumes, which suits the volumes peptide work involves.

The comparison that clarifies it:

• Subcutaneous — into fat, slower uptake, small volumes, the default in most peptide protocols.
• Intramuscular — into muscle, richer blood supply, faster uptake, tolerates larger volumes.

Why it dominates peptide discussion

Most peptides are not orally active — digestion cleaves them before absorption — so injection is the route the literature is written around, and subcutaneous is the one it most often specifies. This is what "pinning" usually refers to in practice.

On technique

Route and technique should follow an established protocol or medical guidance. This page explains what the term means; it is not instruction in how to perform an injection, and none of it is medical advice.

Research use only.