Somatostatin
Also known as: SRIH, GHIF, Growth Hormone Inhibiting Hormone, SST
Overview
Somatostatin is a naturally occurring cyclic 14-amino acid neuropeptide (with an alternate 28-amino acid form) produced in the hypothalamus, pancreas, and gastrointestinal tract. It acts as a broad inhibitor of endocrine and exocrine secretion, suppressing growth hormone, TSH, insulin, glucagon, and multiple GI hormones. Its ultrashort plasma half-life of under three minutes drove the development of longer-acting synthetic analogs including octreotide, lanreotide, and pasireotide that are widely used in clinical practice.
Mechanism of Action
Somatostatin binds five receptor subtypes (SSTR1–SSTR5), all Gi/o-coupled GPCRs. Receptor activation inhibits adenylyl cyclase (reducing cAMP), activates inward-rectifying potassium channels (hyperpolarizing cells), and inhibits voltage-gated calcium channels. These combined effects suppress secretory cell activity across multiple tissues. SSTR2 and SSTR5 are the primary subtypes mediating GH inhibition and are the principal targets of therapeutic analogs.
Potential Benefits
- GH inhibition relevant to acromegaly management (via analogs)
- Glucagon and insulin secretion modulation
- GI motility and secretion regulation
- Neuroendocrine tumor symptom control
- Reduction of splanchnic blood flow in GI bleeding
- Pharmacological template for clinically successful analogs
Dosage Protocols
The following reflects doses used in published research studies. This is not medical advice. Consult a qualified healthcare professional.
| Beginner | Clinical use only |
| Intermediate | N/A |
| Advanced | N/A |
| Cycle Duration | 48-120 hours (acute bleeding protocol) |
Native peptide with 1-3 min half-life — superseded by octreotide for chronic use. Still used IV for variceal bleeding in Europe.
Use our Reconstitution Calculator to determine exact syringe units for your protocol.
Routes of Administration
Continuous Intravenous Infusion 100%
Only practical route due to extremely short half-life.
Read our full Routes of Administration Guide for detailed comparison of all delivery methods.
Stacking Protocols
Popular research stacks involving Somatostatin:
Variceal Bleeding Protocol
European acute variceal bleeding management — clinical use only.
Explore our complete Peptide Stacking Guide for more combinations and safety considerations.
Reconstitution
| Storage | Refrigerate 2-8°C. Use immediately after reconstitution. |
|---|
Clinical IV use only. Not a research/gray-market peptide.
Need exact syringe measurements?
Amino Acid Sequence
Ala-Gly-Cys-Lys-Asn-Phe-Phe-Trp-Lys-Thr-Phe-Thr-Ser-Cys (cyclic, disulfide Cys3-Cys14)
Side Effects & Safety
- Short-term IV use: nausea, diarrhea, abdominal cramping
- Hypoglycemia or hyperglycemia (insulin/glucagon suppression)
- Bradycardia at high doses
Safety & Contraindications
This information is for educational purposes only. Consult a qualified healthcare provider before using any peptide.
Pregnancy / Lactation
Bleeding Disorders
Active Skin Infection at Injection Site
Pharmacokinetics
| Half-Life | Not well characterized for this peptide; consult primary literature |
|---|---|
| Storage | Store lyophilized peptide at -20°C (long-term) or 2-8°C (short-term, under 30 days). Reconstituted: refrigerate at 2-8°C and use within 28-30 days. Protect from light. Do not freeze reconstituted solution. |
Synergistic Compounds
The following compounds have been studied alongside Somatostatin for potential complementary or synergistic effects:
Learn More
References & Further Reading
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