Octreotide Acetate

Indications

Acromegaly: Octreotide acetate injection is indicated to reduce blood levels of growth hormone and IGF-I (somatomedin C) in acromegaly patients who have had inadequate response to or cannot be treated with surgical resection, pituitary irradiation, and bromocriptine mesylate at maximally tolerated doses. The goal is to achieve normalization of growth hormone and IGF-I (somatomedin C) levels. In patients with acromegaly, Octreotide acetate injection reduces growth hormone to within normal ranges in 50% of patients and reduces IGF-I (somatomedin C) to within normal ranges in 50% to 60% of patients. Since the effects of pituitary irradiation may not become maximal for several years, adjunctive therapy with Octreotide acetate injection to reduce blood levels of growth hormone and IGF-I (somatomedin C) offers potential benefit before the effects of irradiation are manifested.

Improvement in clinical signs and symptoms or reduction in tumor size or rate of growth were not shown in clinical trials performed with Octreotide acetate injection; these trials were not optimally designed to detect such effects.

Carcinoid Tumors: Octreotide acetate injection is indicated for the symptomatic treatment of patients with metastatic carcinoid tumors where it suppresses or inhibits the severe diarrhea and flushing episodes associated with the disease.

Octreotide acetate injection studies were not designed to show an effect on the size, rate of growth or development of metastases.

Vasoactive Intestinal Peptide Tumors (VIPomas): Octreotide acetate injection is indicated for the treatment of the profuse watery diarrhea associated with VIP-secreting tumors. Octreotide acetate injection studies were not designed to show an effect on the size, rate of growth or development of metastases.

Pharmacology

Octreotide is a synthetic analogue of somatostatin which acts by suppressing basal and stimulated secretion of growth hormone (GH). It also suppresses LH response to gonadotrophin-releasing hormone and reduces the secretion of gastrin, vasoactive intestinal peptide (VIP), insulin, glucagon, secretin, motilin and pancreatic polypeptide.

Dosage & Administration

Intramuscular-
Acromegaly:
  • Adult: Following initial control with SC therapy: As a depot preparation, initially 20 mg every 4 wk. Adjust if required after 3 mth to 10-30 mg every 4 wk. Max: 40 mg every 4 wk.
Intravenous-
Variceal haemorrhage in patients with cirrhosis:
  • Adult: As continuous IV infusion: 25 mcg/hr for 48 hr (up to 5 days in patients at high risk of re-bleeding).
  • Child: ≥1 mth: 1 mcg/kg/hr (up to 50 mcg/hr); given as continuous IV infusion. Higher doses may be needed initially, reduce dose gradually over 24 hr until bleeding has stopped.
Subcutaneous-
Prophylaxis of complications following pancreatic surgery:
  • Adult: 100 mcg tid of a rapid-acting preparation given for 7 consecutive days, starting at least 1 hr before operation.
Subcutaneous-
Acromegaly:
  • Adult: Initially 50 mcg tid, increased as necessary to usual dose 100-200 mcg tid. Max: 500 mcg tid.
Subcutaneous-
Secretory neoplasms:
  • Adult: Initially, 50 mcg 1-2 times daily, increased gradually to up to 600 mcg daily in 2-4 divided doses according to response. Continued treatment is not recommended if there is no benefit within a wk of starting treatment for carcinoid tumour. Initial dose may be given via IV admin of a rapid response is required.
Subcutaneous-
HIV-associated diarrhoea:
  • Adult: Initial dose 100 mcg tid. If symptoms are not controlled after 1 wk, increase dose to 250 mcg tid, if still not effective after 1 wk stop therapy.

Interaction

Dosage adjustment of concurrent therapy may be necessary with calcium channel blockers, oral hypoglycaemics, β-blockers, diuretics. May increase concentration of bromocriptine.

Contraindications

Hypersensitivity

Side Effects

Local pain, stinging, tingling at site of inj; anorexia, nausea, vomiting, abdominal pain, bloating, flatulence, loose stools, steatorrhoea; biliary tract abnormalities. Hypoglycaemia and hyperglycaemia, hypothyroidism, cardiac conduction abnormalitles, pancreatitis.

Pregnancy & Lactation

Category B: Either animal-reproduction studies have not demonstrated a foetal risk but there are no controlled studies in pregnant women or animal-reproduction studies have shown an adverse effect (other than a decrease in fertility) that was not confirmed in controlled studies in women in the 1st trimester (and there is no evidence of a risk in later trimesters).

Precautions & Warnings

Renal disease; risk of gall bladder disease; DM; hypothyroidism. Pregnancy, lactation, children, elderly. Monitor levels of vitamin B12 during long term therapy.

Use in Special Populations

Renal Impairment: Dosage may need to be reduced in severe renal impairment requiring dialysis.

Therapeutic Class

Growth hormone antagonist

Storage Conditions

Store at 2-8° C. Stable at room temperature for up to 14 days.
Hi, hope you are enjoying MedEx.
Please rate your experience