Octreotide: Uses, Mechanism, and Side Effects

Anyone prescribed octreotide is usually managing a hormone-driven condition like acromegaly or a rare secreting tumor, and wants to know what the drug actually does and what to expect. Octreotide has a long track record: it is a well-established synthetic analogue of a natural hormone, with a substantial body of clinical trial and post-marketing data behind it.

Key takeaways

• Octreotide is a somatostatin analogue marketed as Octreotide Acetate.
• It is approved for acromegaly, metastatic carcinoid tumor symptoms, and VIP-secreting tumors (VIPomas).
• More than 370 registered clinical trials have studied octreotide across these and related conditions.
• The most frequently reported adverse events in FDA safety reports include diarrhea, fatigue, malaise, and nausea.
• Octreotide does not carry a boxed warning.

What Octreotide Is

Octreotide is a synthetic version of somatostatin, a hormone the body uses to regulate other hormones and digestive secretions. It acts as a more potent inhibitor of growth hormone, glucagon, and insulin than the natural hormone itself. Beyond these effects, it reduces blood flow to the gut and suppresses release of serotonin, gastrin, and several other gut hormones. This broad hormonal braking effect is what makes it useful across a handful of distinct, hormone-related conditions.

What Octreotide Is Approved For

Octreotide, sold as Octreotide Acetate, is approved for three main uses. In acromegaly, it lowers growth hormone and IGF-1 levels in patients who have not responded adequately to surgery, radiation, or maximally tolerated bromocriptine. In metastatic carcinoid tumors, it is used to control the severe diarrhea and flushing episodes the disease can cause. It is also approved for the profuse watery diarrhea associated with VIP-secreting tumors (VIPomas). The label notes that improvement in symptoms does not necessarily reflect a reduction in tumor size. Octreotide does not carry a boxed warning.

What the Evidence Shows

Octreotide has been studied in 378 registered clinical trials. A completed phase 2 trial evaluated the safety, efficacy, and pharmacokinetics of a long-acting octreotide injection in patients with acromegaly. Another completed phase 2/3 trial compared a long-acting formulation combined with axitinib against placebo in patients with advanced, well-differentiated non-pancreatic neuroendocrine carcinomas.

Reported Side Effects

Regulatory safety reports for octreotide, which reflect the number of reports submitted rather than confirmed rates of occurrence or direct causation, show a mix of gastrointestinal and general symptoms. Diarrhea is the most frequently reported term, followed by fatigue, malaise, and nausea. Other frequently reported terms include death, increased blood pressure, needle-related issues, and pain. Because these are voluntary reports, they cannot establish that octreotide caused any specific event.