Octreotide – Effects and Dosage

Background

Octreotide is a long-acting drug with pharmacologic activities that mimic those of the natural hormone, somatostatin, which inhibits the secretion of growth hormone.8 Additionally, it is used for the treatment of acromegaly and symptoms arising from various tumors, including carcinoid tumors and vasoactive intestinal tumors (VIPomas).8 In the past, octreotide has been administered solely by injection. On June 26, 2020, the first approved delayed-release oral somatostatin analog, Mycapssa, received FDA approval for the long-term maintenance treatment of acromegaly. This drug was developed by Chiasma Inc.

Properties and Characteristics of Octreotide

Drug class Peptide drug
Brand Names Bynfezia, Mycapssa, Sandostatin
Synonyms Octreotida, Octreotide, Octreotidum, Octrotide
Molecular Formula C49H66N10O10S2
Molecular Weight 1019.2 g/mol
IUPAC Name (4R,7S,10S,13R,16S,19R)-10-(4-aminobutyl)-19-[[(2R)-2-amino-3-phenylpropanoyl]amino]-16-benzyl-N-[(2R,3R)-1,3-dihydroxybutan-2-yl]-7-[(1R)-1-hydroxyethyl]-13-(1H-indol-3-ylmethyl)-6,9,12,15,18-pentaoxo-1,2-dithia-5,8,11,14,17-pentazacycloicosane-4-carboxamide
Structural formula of main components
Pure active ingredient Octreotide
Appearance Solution for injection is clear and colourless.
Melting point 153-156 °C
Solubility 0.0122 mg/mL
Excretion Oral octreotide dose is excreted into the urine
Storage Refrigerate at 2°C to 8°C (36°F to 46°F); protect from light.
Available Forms Injection, powder, for suspension and Solution
Prescription   Doctor prescription is required

What is Octreotide injection used for?

  • Acromegaly
  • Diarrhea and flushing linked to carcinoid tumors
  • Diarrhea linked to vasoactive instestinal peptide tumors (VIPomas)

What side effects can this medication cause?

This medication may cause changes in your blood sugar. You should know the symptoms of high and low blood sugar and what to do if you have these symptoms.

Octreotide injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • Diarrhea
  • Constipation
  • Pale, bulky, foul-smelling stools
  • Constantly feeling the need to empty the bowels
  • Gas
  • Stomach pain
  • Nausea
  • Heartburn
  • Headache
  • Dizziness
  • Tiredness
  • Back, muscle, or joint pain
  • Nosebleed
  • Hair loss
  • Pain in the area where the medication was injected
  • Vision changes

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately:

  • Pain in the upper right part of the stomach, center of the stomach, back, or shoulder
  • Yellowing of the skin or eyes
  • Slowed or irregular heartbeat
  • Sluggishness
  • Sensitivity to cold
  • Pale, dry skin
  • Brittle fingernails and hair
  • Puffy face
  • Hoarse voice
  • Depression
  • Heavy menstrual periods
  • Swelling at the base of the neck
  • Tightness in the throat
  • Difficulty breathing and swallowing
  • Rash
  • Itching

Octreotide injection may cause other side effects. Call your doctor if you have any unusual problems while receiving this medication.

Mechanism of action

Octreotide binds to somatostatin receptors coupled to phospholipase C through G proteins and leads to smooth muscle contraction in the blood vessels. Downstream effects that stimulate phospholipase C, the production of 1, 4,5-inositol triphosphate, and action on the L-type calcium channels lead to the inhibition of growth hormone, treating the various growth-hormone and metabolic effects of acromegaly.

Octreotide’s suppression of luteinizing hormone (LH)3, reduction in splanchnic blood flow4, and inhibition of serotonin, gastrin, vasoactive intestinal peptide, secretin, motilin, and pancreatic polypeptide provide relief for the gastrointestinal and flushing symptoms of carcinoid and/or VIPoma tumors.

Drug Interactions

Octreotide has been associated with alterations in nutrient absorption, so it may have an effect on absorption of orally administered drugs. Concomitant administration of octreotide acetate injection with cyclosporine may decrease blood levels of cyclosporine and result in transplant rejection.

Patients receiving insulin, oral hypoglycemic agents, beta blockers, calcium channel blockers, or agents to control fluid and electrolyte balance, may require dose adjustments of these therapeutic agents.

Concomitant administration of octreotide and bromocriptine increases the availability of bromocriptine. Limited published data indicate that somatostatin analogs might decrease the metabolic clearance of compounds known to be metabolized by cytochrome P450 enzymes, which may be due to the suppression of growth hormone (GH). Since it cannot be excluded that octreotide may have this effect, other drugs mainly metabolized by CYP3A4 and which have a low therapeutic index (e.g., quinidine, terfenadine) should therefore be used with caution.

Octreotide competitively binds to somatostatin receptors and may interfere with the efficacy of lutetium Lu 177 dotatate. Discontinue octreotide acetate Injection at least 24 hours prior to each lutetium Lu 177 dotatate dose.

Typical dosing for Octreotide injection

Your provider will adjust your dose of octreotide injection based on symptoms and lab results for the condition you’re being treated for.

  • Acromegaly: The typical starting dose is 50 mcg injected under the skin 3 times per day. The typical maintenance dose is 100 mcg injected 3 times per day.
  • Carcinoid tumors: The typical starting dose is 100 mcg to 600 mcg daily total, injected under the skin in 2 to 4 divided doses. The typical maintenance dose is around 450 mcg daily total, injected in divided doses.
  • Vasoactive intestinal peptide tumors (VIPomas): The typical starting dose is 200 mcg to 300 mcg daily total, injected under the skin in 2 to 4 divided doses. The typical maintenance dose is 150mcg to 450 mcg daily total, injected in divided doses.

Octreotide injection can also be given intravenously by a healthcare provider.

Overdose Symptoms

Octreotide is a medication primarily used to treat various medical conditions, including acromegaly, carcinoid syndrome, and certain types of tumors. Like any medication, it can be associated with the risk of overdose. Overdosing on octreotide can lead to a range of symptoms, which may vary in severity depending on the amount ingested and individual factors. If you suspect an octreotide overdose, you should seek immediate medical attention or contact a poison control center. Here are some potential symptoms of an octreotide overdose:

  1. Gastrointestinal: Nausea, vomiting, diarrhea, abdominal pain.
  2. Cardiovascular: Bradycardia, hypotension, arrhythmias.
  3. Neurological: Dizziness, weakness, headache, confusion, rare seizures.
  4. Respiratory: Breathing difficulties.
  5. Metabolic: Hypo/hyperglycemia, electrolyte imbalances.

Octreotide is mainly administered by healthcare professionals with controlled dosages. If overdose is suspected, seek immediate medical attention. Follow prescribed dosages to prevent overdose and complications.

Precautions and Warnings

Octreotide is a medication used to treat various medical conditions, but it comes with certain warnings and precautions that should be considered before and during its use. It’s essential to follow your healthcare provider’s guidance and discuss any concerns you may have. Here are some key warnings and precautions associated with octreotide:

Allergic Reactions: Before using octreotide, inform your healthcare provider if you are allergic to it or any other medications. Seek immediate medical attention if you experience signs of an allergic reaction, such as rash, itching, swelling, severe dizziness, or difficulty breathing.

Liver and Kidney Function: Inform your healthcare provider about any pre-existing liver or kidney conditions, as octreotide may affect these organs. Regular monitoring of liver and kidney function may be necessary during treatment.

Gallstones: Octreotide can increase the risk of gallstone formation. If you have a history of gallstones or related problems, discuss this with your healthcare provider before starting octreotide.

Blood Sugar Levels: Octreotide can affect blood sugar levels. If you have diabetes or are at risk of developing diabetes, your healthcare provider may need to adjust your diabetes medications while you are on octreotide.

Thyroid Function: Octreotide can affect thyroid function tests, potentially leading to abnormal results. Inform your healthcare provider if you are undergoing thyroid function testing while on octreotide.

Heart and Cardiac Arrhythmias: Octreotide may lead to heart rate changes and cardiac arrhythmias. It should be used cautiously in individuals with a history of heart problems or arrhythmias.

Pregnancy and Breastfeeding: If you are pregnant or planning to become pregnant, discuss the risks and benefits of octreotide with your healthcare provider. It is not well-studied during pregnancy, and the potential risks should be carefully considered. It is not recommended during breastfeeding, as it may pass into breast milk.

Interactions: Octreotide may interact with other medications you are taking, potentially affecting their effectiveness or causing adverse effects. Inform your healthcare provider of all medications, supplements, and herbal products you are using.

Injection Site Reactions: If octreotide is administered by injection, be aware of possible injection site reactions such as pain, swelling, and redness. Rotate injection sites as directed by your healthcare provider to minimize discomfort.

Tumor Growth: Octreotide is used to treat certain tumors, but it may not work for all types. Your healthcare provider will monitor your condition to assess the medication’s effectiveness. Do not use octreotide for conditions for which it is not prescribed.

Always follow your healthcare provider’s instructions and guidance when taking octreotide. If you have questions or concerns about its use, discuss them with your healthcare provider to ensure safe and effective treatment.

Leave a Reply

Your email address will not be published. Required fields are marked *