Why Most Peptides Are Injected
Most therapeutic peptides are administered by subcutaneous injection because oral bioavailability is poor — stomach acid degrades the peptide before it can be absorbed. Subcutaneous injection delivers the compound into the fatty tissue just below the skin, where it is absorbed into the bloodstream efficiently.
What Your Physician Will Teach You
Before beginning a self-injection protocol, your physician or their support team will walk you through the complete process: how to reconstitute lyophilized (freeze-dried) peptides with bacteriostatic water, how to draw and measure doses accurately, proper injection site selection and rotation, sterile technique to prevent infection, and how to store your medication.
Common Injection Sites
Subcutaneous injections for peptide therapy are typically administered in the abdomen (2-3 inches from the navel), the outer thigh, or the back of the upper arm. Sites should be rotated to prevent tissue irritation or lumps (lipohypertrophy) from repeated injections at the same location.
Reconstitution
Lyophilized peptides must be reconstituted with bacteriostatic water before injection. Your physician will specify the exact volume to use based on your prescribed dose. Reconstituted peptides are typically stored refrigerated and have a limited stability window — usually 28-60 days depending on the compound and storage conditions.
What Most Patients Experience
Most patients find subcutaneous injections significantly less painful than anticipated. The needles used (typically 29-31 gauge, 1/2 inch) are very fine. Minor stinging or redness at the injection site is normal and resolves quickly. Significant pain, swelling, or redness warrants contact with your care coordinator.