Bynfezia Pen

Last updated on RxList: 7/21/2021
Bynfezia Pen Side Effects Center

Medical Editor: John P. Cunha, DO, FACOEP

What Is Bynfezia Pen?

Bynfezia Pen (octreotide acetate) is a somatostatin analogue indicated for reduction of growth hormone (GH) and insulin-like growth factor 1 (IGF-1) [somatomedin C] in adult patients with acromegaly who have had inadequate response to or cannot be treated with surgical resection, pituitary irradiation, and bromocriptine mesylate at maximally tolerated doses; treatment of severe diarrhea/flushing episodes associated with metastatic carcinoid tumors in adult patients; and treatment of profuse watery diarrhea associated with vasoactive intestinal peptide tumors (VIPomas) in adult patients.

What Are Side Effects of Bynfezia Pen?

Side effects of Bynfezia Pen include:

Dosage for Bynfezia Pen

The initial dose of Bynfezia Pen to treat acromegaly is 50 mcg three times daily. The typical dosage of Bynfezia Pen to treat acromegaly is 100 mcg three times a day. The dose of Bynfezia Pen to treat carcinoid tumor is 100-600 mcg daily in 2-4 divided doses for first 2 weeks. The dose of Bynfezia Pen to treat VIPomas is 200-300 mcg daily in 2-4 divided doses for first 2 weeks.

Bynfezia Pen in Children

Safety and efficacy of Bynfezia Pen in pediatric patients have not been established.

What Drugs, Substances, or Supplements Interact with Bynfezia Pen?

Bynfezia Pen may interact with other medicines such as:

  • cyclosporine,
  • bromocriptine,
  • insulin and oral hypoglycemic drugs,
  • calcium channel blockers,
  • beta blockers,
  • drugs to control fluid and electrolyte balance, and
  • quinidine

Tell your doctor all medications and supplements you use.

Bynfezia Pen During Pregnancy and Breastfeeding

Tell your doctor if you are pregnant or plan to become pregnant before using Bynfezia Pen; it is unknown how it would affect a fetus. There is the potential for unintended pregnancy with premenopausal women as the therapeutic benefits of a reduction in GH levels and normalization of IGF-1 concentration in acromegalic females treated with Bynfezia Pen may lead to improved fertility. It is unknown if Bynfezia Pen passes into breast milk. Consult your doctor before breastfeeding.

Additional Information

Our Bynfezia Pen (octreotide acetate) Injection, for Subcutaneous Use Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication. This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.


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Bynfezia Pen Consumer Information

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • severe constipation;
  • slow or uneven heartbeats;
  • signs of gallstones--fever, chills, nausea, vomiting, severe pain in your upper stomach spreading to your back, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes);
  • high blood sugar--increased thirst, increased urination, dry mouth, fruity breath odor;
  • low blood sugar--headache, hunger, sweating, irritability, dizziness, fast heart rate, and feeling anxious or shaky; or
  • underactive thyroid--extreme tired feeling, dry skin, joint pain or stiffness, muscle pain or weakness, hoarse voice, feeling more sensitive to cold temperatures, weight gain.

Common side effects may include:

  • gallstones;
  • nausea, vomiting, diarrhea, stomach pain, gas;
  • headache, back pain; or
  • dizziness, tiredness.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Read the entire detailed patient monograph for Bynfezia Pen (Octreotide Acetate Injection, for Subcutaneous Use)

Bynfezia Pen Professional Information


The following important adverse reactions are described below and elsewhere in the labeling:

  • Cholelithiasis and Complications of Cholelithiasis [see WARNINGS AND PRECAUTIONS]
  • Hyperglycemia and Hypoglycemia [see WARNINGS AND PRECAUTIONS]
  • Thyroid Function Abnormalities [see WARNINGS AND PRECAUTIONS]
  • Cardiac Function Abnormalities [see WARNINGS AND PRECAUTIONS]
  • Decreased Vitamin B12 Levels and Abnormal Schilling’s Tests [see WARNINGS AND PRECAUTIONS]

Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trial of another drug and may not reflect the rates observed in practice.

The safety of BYNFEZIA Pen has been established based on clinical studies of octreotide acetate injection. Below is a description of the adverse reactions from the clinical studies.

Gallbladder Abnormalities

Gallbladder abnormalities, especially stones and/or biliary sludge, frequently develop in patients on chronic octreotide therapy. Single doses of octreotide have been shown to inhibit gallbladder contractility and decrease bile secretion in normal volunteers. In clinical trials [primarily patients with acromegaly or psoriasis (BYNFEZIA Pen is not indicated for the treatment of psoriasis)], the incidence of biliary tract abnormalities was 63% (27% gallstones, 24% sludge without stones, 12% biliary duct dilatation). The incidence of stones or sludge in patients who received octreotide for 12 months or longer was 52%. Less than 2% of patients treated with octreotide for 1 month or less developed gallstones. The incidence of gallstones did not appear related to age, sex or dose. Like patients without gallbladder abnormalities, the majority of patients developing gallbladder abnormalities on ultrasound had gastrointestinal symptoms. The symptoms were not specific for gallbladder disease. A few patients developed acute cholecystitis, ascending cholangitis, biliary obstruction, cholestatic hepatitis, or pancreatitis during octreotide therapy or following its withdrawal. One patient developed ascending cholangitis during octreotide therapy and died.


In acromegalics, sinus bradycardia (<50 bpm) developed in 25%; conduction abnormalities occurred in 10% and arrhythmias developed in 9% of patients.


Diarrhea, loose stools, nausea and abdominal discomfort were each seen in 34%-61% of acromegalic patients in U.S. studies although only 2.6% of the patients discontinued therapy due to these symptoms. These symptoms were seen in 5%-10% of patients with other disorders.

The frequency of these symptoms was not dose-related, but diarrhea and abdominal discomfort generally resolved more quickly in patients treated with 300 mcg/day than in those treated with 750 mcg/day. Vomiting, flatulence, abnormal stools, abdominal distention, and constipation were each seen in less than 10% of patients.

In rare instances, gastrointestinal side effects may resemble acute intestinal obstruction, with progressive abdominal distension, severe epigastric pain, abdominal tenderness and guarding.

Hypoglycemia And Hyperglycemia

Hypoglycemia and hyperglycemia occurred in 3% and 16% of acromegalic patients, respectively, and in about 1.5% of other patients. Symptoms of hypoglycemia were noted in approximately 2% of patients.


In acromegalics, biochemical hypothyroidism alone occurred in 12% while goiter occurred in 6% during octreotide therapy. In patients without acromegaly, hypothyroidism has been reported in several patients.

Other Adverse Reactions

Pain on injection was reported in 7.7%, headache in 6% and dizziness in 5%. Several cases of pancreatitis have been reported.

Other Adverse Reactions 1%-4%

Other reactions observed in 1%-4% of patients, included fatigue, weakness, pruritus, joint pain, backache, urinary tract infection, cold symptoms, flu symptoms, injection site hematoma, bruise, edema, flushing, blurred vision, pollakiuria, fat malabsorption, hair loss, visual disturbance and depression.

Other Adverse Reactions <1%

Reactions reported in less than 1% of patients are:

Gastrointestinal: hepatitis, jaundice, increase in liver enzymes, GI bleeding, hemorrhoids, appendicitis, gastric/peptic ulcer, gallbladder polyp;

Integumentary: rash, cellulitis, petechiae, urticaria, basal cell carcinoma;

Musculoskeletal: arthritis, joint effusion, muscle pain, Raynaud’s phenomenon;

Cardiovascular: chest pain, shortness of breath, thrombophlebitis, ischemia, congestive heart failure, hypertension, hypertensive reaction, palpitations, orthostatic BP decrease, tachycardia;

CNS: anxiety, libido decrease, syncope, tremor, seizure, vertigo, Bell’s Palsy, paranoia, pituitary apoplexy, increased intraocular pressure, amnesia, hearing loss, neuritis;

Respiratory: pneumonia, pulmonary nodule, status asthmaticus;

Endocrine: galactorrhea, hypoadrenalism, diabetes insipidus, gynecomastia, amenorrhea, polymenorrhea, oligomenorrhea, vaginitis;

Urogenital: nephrolithiasis, hematuria;

Hematologic: anemia, iron deficiency, epistaxis;

Miscellaneous: otitis, allergic reaction, increased CK, weight loss.

Antibodies to Octreotide

Evaluation of 20 patients treated for at least 6 months has failed to demonstrate titers of antibodies exceeding background levels. However, antibody titers to octreotide were subsequently reported in three patients and resulted in prolonged duration of drug action in two patients. Anaphylactoid reactions, including anaphylactic shock, have been reported in several patients receiving octreotide.

Postmarketing Experience

The following adverse reactions have been identified during the postapproval use of octreotide acetate injection. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

Gastrointestinal: intestinal obstruction

Hematologic: thrombocytopenia



Concomitant administration of BYNFEZIA Pen with cyclosporine may decrease blood levels of cyclosporine and result in transplant rejection.

Insulin And Oral Hypoglycemic Drugs

Octreotide inhibits the secretion of insulin and glucagon. Monitor blood glucose levels upon BYNFEZIA Pen initiation or dose adjustment. Patients with diabetes mellitus may require dose adjustments of insulin or other antidiabetic agents [see WARNINGS AND PRECAUTIONS].


Concomitant administration of BYNFEZIA Pen and bromocriptine increases the availability of bromocriptine.

Other Concomitant Drug Therapy

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

Octreotide has been associated with alterations in nutrient absorption, so it may have an effect on absorption of orally administered drugs.

Drug Metabolism Interactions

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 hormones. Since octreotide may have this effect, concomitant use of BYNFEZIA Pen with other drugs mainly metabolized by CYP3A4 and which have a low therapeutic index (e.g., quinidine) should be used with caution and increased monitoring may be required.

Read the entire FDA prescribing information for Bynfezia Pen (Octreotide Acetate Injection, for Subcutaneous Use)

© Bynfezia Pen Patient Information is supplied by Cerner Multum, Inc. and Bynfezia Pen Consumer information is supplied by First Databank, Inc., used under license and subject to their respective copyrights.

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