Quick answer: what is Octreotide?
Octreotide is a long-acting synthetic version of the natural hormone somatostatin, used to switch off the excess secretion of growth hormone and other hormones.
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Quick facts
- Class
- Somatostatin analog (octapeptide)
- Brand names
- Sandostatin, Sandostatin LAR
- Approved for
- Acromegaly, carcinoid syndrome, VIPoma, variceal bleeding
- Administration
- Subcutaneous injection or long-acting monthly depot
- Status
- FDA-approved, prescription-only
- Targets
- Somatostatin receptors (mainly SSTR2, SSTR5)
- First approved
- Late 1980s
- Notable risk
- Gallstones; blood-sugar changes
Key takeaways
- It is FDA-approved for acromegaly, carcinoid syndrome, and other neuroendocrine tumor conditions, and is also used in acute variceal bleeding.
- It comes as a short-acting injection and as a long-acting monthly depot (Sandostatin LAR).
- A characteristic long-term risk is gallstones, because it suppresses gallbladder emptying.
Overview
Octreotide is a synthetic, eight-amino-acid analog of somatostatin — the body's general-purpose inhibitory hormone. Somatostatin is sometimes described as the endocrine system's brake pedal: it is released in the hypothalamus, pancreas, and gut, and it switches off the secretion of a long list of other hormones, including growth hormone, insulin, glucagon, and gastrin. The problem with using natural somatostatin as a medicine is that the body destroys it within about two minutes. Octreotide was engineered around that limitation, retaining the parts of the molecule that bind the receptor while resisting the enzymes that break it down.
The result is a drug that reproduces somatostatin's key inhibitory effects but lasts for hours in its standard form and for weeks in its depot form. Approved in the late 1980s, it was one of the earliest peptide analogs to succeed commercially and it remains a fixture of endocrinology and oncology decades later.
Where it fits clinically
Octreotide is used when a gland or tumor is producing too much of something. In acromegaly, that is growth hormone from a pituitary tumor. In carcinoid syndrome, it is the flood of serotonin and other mediators from a neuroendocrine tumor that causes flushing and severe diarrhea. In a VIPoma, it is vasoactive intestinal peptide driving watery diarrhea. In every case the logic is the same: apply the brake.
This is worth stating plainly because octreotide is occasionally mentioned in peptide discussions as though it belonged to the same category as unapproved research compounds. It does not. It is a specialist prescription medicine with decades of clinical use, formal labeling, and a well-characterized side-effect profile.
How it works
There are five somatostatin receptor subtypes, labeled SSTR1 through SSTR5, and they are distributed differently across tissues. Octreotide does not bind all five equally — it has high affinity for SSTR2, moderate affinity for SSTR5, and comparatively little for the others. That binding pattern explains both what the drug does well and where it falls short.
The downstream effects
- Hormone suppression. Activating SSTR2 on pituitary cells reduces growth hormone release, which in turn lowers liver production of IGF-1, the hormone that mediates most of growth hormone's effects on tissue.
- Gut and pancreatic effects. The same receptors on pancreatic and intestinal cells suppress insulin, glucagon, gastrin, and vasoactive intestinal peptide, and slow gastrointestinal motility.
- Reduced splanchnic blood flow. Octreotide constricts the circulation supplying the gut, which is the basis for its use in bleeding from esophageal varices.
- Antiproliferative signaling. Somatostatin receptors on tumor cells can trigger growth-arrest signaling, meaning the drug does more than mask symptoms in some neuroendocrine tumors.
Why receptor selectivity matters
Because octreotide concentrates its activity on SSTR2, it works well where SSTR2 is abundant and poorly where it is not. The classic example is Cushing's disease, where the responsible pituitary tumors express mainly SSTR5. That gap is precisely why pasireotide, a broader-spectrum analog, was developed. Understanding this one point explains most of the differences between the somatostatin drugs.
Clinical uses & evidence
Acromegaly
Acromegaly is caused by a growth-hormone-secreting pituitary tumor, and surgery is the first-line treatment. When surgery does not fully control the disease — a common outcome with larger tumors — octreotide is a standard medical option. The long-acting release depot normalizes growth hormone and IGF-1 in a substantial proportion of patients and reduces the soft-tissue symptoms, headache, and joint pain that accompany the condition. Response varies with tumor receptor expression, which is why some patients do well and others need a different drug or a different class entirely.
Carcinoid syndrome and neuroendocrine tumors
Functioning neuroendocrine tumors release hormones that cause debilitating flushing and diarrhea. Octreotide blunts that release and is a mainstay of symptom control. Beyond symptoms, somatostatin analogs as a class have been shown to slow tumor progression in certain neuroendocrine tumor settings, which shifted them from purely supportive therapy toward genuine antitumor treatment. It is also used to prevent and manage carcinoid crisis around surgery and other procedures.
Other established uses
Octreotide is used in acute variceal bleeding to reduce portal pressure and splanchnic blood flow, and in severe secretory diarrheas including those associated with VIPoma, chemotherapy, and HIV. It has a role in managing chylothorax, high-output fistulas, and dumping syndrome, and in sulfonylurea overdose, where suppressing insulin release is the point.
How to read the evidence
Octreotide's evidence base is unusual for a peptide covered on this site: it consists of randomized trials, decades of registry data, and formal regulatory review, not preclinical work or extrapolation. When we describe the evidence tier for octreotide as approved-medicine grade, that reflects a genuinely different quality of information than exists for most research peptides.
Forms & how it's given
Octreotide comes in two practically different forms. The immediate-release solution is given by subcutaneous injection several times a day and acts within hours. The long-acting release depot is injected into muscle roughly once a month and maintains steady levels between doses.
Treatment typically starts with the short-acting form. That is not arbitrary: it lets the specialist confirm that the patient responds and tolerates the drug before committing to a depot that cannot be withdrawn quickly. Once response is established, most patients transition to the monthly depot for convenience, sometimes with short-acting doses used for breakthrough symptoms.
Dose selection depends on the condition, the biochemical response, and tolerance, and is adjusted over time based on hormone levels and imaging. Some formulations require refrigeration and specific reconstitution procedures performed by trained staff.
We do not publish dosing protocols. Octreotide is a prescription medicine whose dosing is individualized by an endocrinologist or oncologist against laboratory monitoring, and there is no meaningful consumer dosing to describe.
Safety & legal status
Octreotide is generally well tolerated, but it has a characteristic set of side effects that follow directly from its mechanism.
- Gallbladder problems. By suppressing gallbladder contraction, octreotide promotes sludge and gallstone formation. This is common with long-term therapy and is the reason periodic gallbladder imaging is part of routine monitoring.
- Gastrointestinal effects. Nausea, abdominal cramping, bloating, loose stools, and fat malabsorption are frequent early on and often ease with continued treatment.
- Blood-sugar changes. Because the drug suppresses both insulin and glucagon, glucose can move in either direction. Patients with diabetes may need their treatment adjusted.
- Slowed heart rate and conduction effects can occur, particularly in patients with underlying cardiac disease.
- Thyroid and vitamin B12 levels can drift with long-term use and are monitored periodically.
- Injection-site reactions are common with the depot form.
Legal status
Octreotide is an FDA-approved, prescription-only medicine, available as branded and generic products through the regulated pharmacy supply chain. It is not sold as a research chemical, and there is no legitimate consumer route to obtaining it. Anyone taking octreotide is doing so under specialist supervision with regular biochemical monitoring, which is an appropriate reflection of the conditions it treats.
The somatostatin analogs compared
All three mimic somatostatin, the body's broad "off switch" hormone. What separates them is which receptor subtypes they reach — which in turn decides what each one can treat.
| Octreotide | Lanreotide | Pasireotide | |
|---|---|---|---|
| Generation | First | First | Second (broad-spectrum) |
| Main receptors | SSTR2, some SSTR5 | SSTR2, some SSTR5 | SSTR1, 2, 3 and especially SSTR5 |
| Approved for | Acromegaly, carcinoid syndrome, VIPoma | Acromegaly, gastroenteropancreatic neuroendocrine tumours | Cushing's disease, acromegaly |
| Administration | Subcutaneous injection; monthly intramuscular depot | Deep subcutaneous prefilled gel, ~monthly | Twice-daily subcutaneous; monthly long-acting |
| Distinctive strength | Longest track record, most indications | Simple prefilled depot; antitumour benefit shown in CLARINET | Reaches ACTH-secreting pituitary tumours the others miss |
| Distinctive drawback | Gallstones with long-term use | Similar class effects; fewer non-endocrine uses | Marked hyperglycaemia in most patients |
| Status | FDA-approved | FDA-approved | FDA-approved |
Frequently asked questions
What is octreotide used for?
Octreotide is used to control conditions of hormone excess and hormone-secreting tumors — chiefly acromegaly, carcinoid syndrome, and neuroendocrine tumors — and also to reduce bleeding from esophageal varices. It works by suppressing the release of growth hormone and various gut and pancreatic hormones.
Is octreotide the same as lanreotide?
They are closely related somatostatin analogs with very similar uses and mechanisms. Octreotide (Sandostatin) was first; lanreotide (Somatuline) is a later analog given as a monthly deep subcutaneous depot. Choice between them often comes down to formulation and individual response.
What are the main side effects of octreotide?
Common effects include gastrointestinal upset, and with long-term use an increased risk of gallstones because octreotide suppresses gallbladder contraction. It can also disturb blood-sugar control by altering insulin and glucagon. It is used under specialist supervision.
Is octreotide FDA-approved?
Yes. Octreotide is an FDA-approved, prescription-only medicine, available as short-acting Sandostatin and long-acting Sandostatin LAR. It is not a research chemical or supplement.
References
Each source links to its original record — peer-reviewed studies, regulator pages, or reference texts, labelled by type. We summarize findings neutrally; a citation is a reference, not an endorsement, and not a claim that its authors reviewed this page.
- McKeage K, Cheer S, Wagstaff AJ. Octreotide long-acting release (LAR): a review of its use in the management of acromegaly. Drugs. 2003. Peer-reviewed study
- Katz MD, Erstad BL. Octreotide, a new somatostatin analogue. Clin Pharm. 1989. Peer-reviewed study
- Cives M, Strosberg JR. Gastroenteropancreatic Neuroendocrine Tumors. CA Cancer J Clin. 2018. Peer-reviewed study
- Yang LP, Keating GM. Octreotide long-acting release (LAR): a review of its use in the management of acromegaly. Drugs. 2010. Peer-reviewed study
- Saif MW, Parikh R, Ray D, et al.. Medical record review of transition to lanreotide following octreotide for neuroendocrine tumors. J Gastrointest Oncol. 2019. Peer-reviewed study
- Turner HE, Vadivale A, Keenan J, et al.. A comparison of lanreotide and octreotide LAR for treatment of acromegaly. Clin Endocrinol (Oxf). 1999. Peer-reviewed study
- Chanson P, Boerlin V, Ajzenberg C, et al.. Comparison of octreotide acetate LAR and lanreotide SR in patients with acromegaly. Clin Endocrinol (Oxf). 2000. Peer-reviewed study
- Tutuncu Y, Berker D, Isik S, et al.. Comparison of octreotide LAR and lanreotide autogel as post-operative medical treatment in acromegaly. Pituitary. 2012. Peer-reviewed study
- Turner HE, Lindsell DR, Vadivale A, et al.. Differing effects on gall-bladder motility of lanreotide SR and octreotide LAR for treatment of acromegaly. Eur J Endocrinol. 1999. Peer-reviewed study
- Kiesewetter B, Pflüger FF, Melhorn P, et al.. Long-term experience with octreotide and lanreotide for the treatment of gastroenteropancreatic neuroendocrine tumors. Clin Transl Oncol. 2025. Peer-reviewed study
- Wang L, Chen S, Wu M, et al.. Comparative analysis of adverse event profiles of lanreotide and octreotide in somatostatin-responsive endocrine and neoplastic diseases. Sci Rep. 2025. Peer-reviewed study
- Zhao Y, Tao Y, Zhu Y, et al.. Comparison of somatostatin analogues on glucose metabolism: A systematic review and network Meta-Analysis of randomized controlled trials. Endocrine. 2026. Peer-reviewed study