Peptide Schedule
Somatostatin (SST-14 and SST-28)14 residuesAGCKNFFWKTFTSCEach bubble = one amino acid. Size = residue mass. Color = chemical class.Somatostatin (SST-14 and SST-28) Dosage Calculator
Somatostatin (somatotropin release-inhibiting factor, SRIF) is a cyclic peptide hormone first isolated from ovine hypothalamic extracts by Roger Guillemin's laboratory in 1973.
100mcg · Daily
Summary: Add 2mL BAC water to your 0.25mg vial. Draw to 80.0 units on a U-100 syringe for a 100mcg dose. This vial will last 2 doses.
Cycle Planner
Somatostatin (SST-14 and SST-28) Pharmacokinetics
Pharmacokinetics — Active Dose Over Time
t½ = ~1-3 minutes (IV); SST-28 ~2-3x longer than SST-14Disclaimer: This curve is a simplified first-order exponential decay model. Actual pharmacokinetics vary based on injection site, individual metabolism, body composition, and other factors. Half-life values are approximate and based on available preclinical and clinical literature. Many research peptides lack formal human pharmacokinetic studies. This is for educational purposes only — not medical advice.
Somatostatin (SST-14 and SST-28) Dosing Protocol
| Level | Dose / Injection | Frequency |
|---|---|---|
| Beginner | 100mcg | Daily |
| Moderate | 250mcg | Daily |
| Aggressive | 500mcg | Daily |
Note: Somatostatin (SRIF, somatotropin release-inhibiting factor) is the endogenous cyclic peptide hormone produced in the hypothalamus, GI tract, and pancreatic delta cells. It exists in two bioactive forms: SST-14 (14 amino acids) and SST-28 (N-terminally extended 28 amino acids). Native somatostatin itself has an extremely short half-life of approximately 1-3 minutes IV, which renders it impractical for routine clinical use. This ultrashort duration of action is the primary reason synthetic analogs — octreotide, lanreotide, and pasireotide — were developed with engineered metabolic stability. Native somatostatin is primarily used in research settings and specialized diagnostic/provocative tests (e.g., somatostatin infusion test for insulinoma). The dosing tiers shown reflect research and diagnostic infusion protocols only. This peptide is NOT a standard therapeutic agent; patients requiring somatostatin-like therapy should use FDA-approved analogs. All use should be under direct medical supervision in a clinical setting.
About Somatostatin (SST-14 and SST-28)
Somatostatin (somatotropin release-inhibiting factor, SRIF) is a cyclic peptide hormone first isolated from ovine hypothalamic extracts by Roger Guillemin's laboratory in 1973. It exists in two principal bioactive forms: SST-14, a 14-amino-acid cyclic peptide with a disulfide bridge between Cys3 and Cys14, and SST-28, an N-terminally extended 28-amino-acid form that includes the full SST-14 sequence at its C-terminus. Both forms are generated by proteolytic processing of a 116-amino-acid precursor, preprosomatostatin. Somatostatin is produced in multiple tissues throughout the body: hypothalamic neurons of the periventricular nucleus (where it acts as the primary inhibitor of pituitary growth hormone release), delta cells of the pancreatic islets (regulating insulin and glucagon secretion in a paracrine manner), and D cells scattered throughout the gastrointestinal mucosa (suppressing gastric acid, pepsin, gastrin, secretin, cholecystokinin, and other GI hormones). It also functions as a neurotransmitter in the central nervous system, with roles in cognition, pain modulation, and motor activity. The peptide binds to five G protein-coupled receptor subtypes (SSTR1 through SSTR5) with varying affinities. SST-14 binds all five subtypes with roughly equal affinity, while SST-28 shows preferential binding to SSTR5. These receptors are widely distributed across the brain, pituitary, pancreas, GI tract, immune cells, and various tumors — particularly neuroendocrine tumors that overexpress SSTR2. The critical limitation of native somatostatin is its ultrashort plasma half-life of approximately 1 to 3 minutes following intravenous administration, due to rapid enzymatic degradation by endopeptidases in blood and tissues. This necessitated the development of metabolically stable synthetic analogs: octreotide (half-life ~1.8 hours), lanreotide (half-life ~23-30 days for depot), and pasireotide (half-life ~12 hours), which selectively target subsets of somatostatin receptors with dramatically extended durations of action. Despite its impracticality as a therapeutic agent, native somatostatin remains an important research tool and has been used clinically in specialized settings, including continuous IV infusion for acute variceal hemorrhage (largely superseded by octreotide), diagnostic provocative testing for insulinoma, and investigational studies of hormone secretion physiology.