Intravenous (IV)
Definition
Administration directly into a vein. Provides 100% bioavailability but requires medical supervision and sterile technique.
Related Terms in Administration
Subcutaneous (SubQ)
An injection administered into the fatty tissue layer between the skin and muscle. The most common route for peptide self-administration.
Intramuscular (IM)
An injection administered directly into a muscle. Some peptides may be administered via IM injection under medical supervision.
Intranasal
Administration through the nasal mucosa. Some peptides (Semax, Selank, oxytocin) are administered intranasally to bypass GI degradation and potentially access the blood-brain barrier more directly.
Sublingual
Administration under the tongue where the substance is absorbed through the oral mucosa directly into the bloodstream, partially bypassing first-pass metabolism. Some peptides are explored via this route.
Topical Peptide
A peptide formulated for application directly to the skin, often in creams, serums, or patches. Copper peptides (GHK-Cu) and cosmetic peptides (SNAP-8, Matrixyl) are common topical formulations. Skin penetration is limited for most peptides without penetration enhancers.
Transdermal
Delivery of a substance through the skin into systemic circulation, typically via patches or specialized creams. Peptides generally have poor transdermal absorption due to their size, though emerging technologies like microneedle patches aim to overcome this.
Microneedle Patch
An emerging delivery technology using tiny needles that painlessly penetrate the skin barrier to deliver peptides. Still largely experimental but may offer a needle-free alternative to subcutaneous injection.
Insulin Syringe
A syringe calibrated in units (typically 100 units per mL) designed for precise measurement of small volumes. Commonly used for peptide administration.