Octreotide Bromocriptine

Other neuromodulatory agents include bromocriptine, cabergoline, valproic acid, octreotide, and rosiglitazone. 

A dopamine agonist alone or in combination with pituitary surgery, radiation therapy, or octreotide administration can be used to treat acromegaly. The doses required are higher than those used to treat hyperprolactinemia. For example, patients with acromegaly require 20-30 mg/d of bromocriptine and seldom respond adequately to bromocriptine alone unless the pituitary tumor secretes prolactin as well as GH. 

BROMOCRIPTINE HORMONE ANTAGONISTS -OCTREOTIDE t bromocriptine levels Uncertain Be aware... 

In acromegaly, excess growth hormone causes diabetes, hypertension and arthritis. The former two lead to a 2-fold excess in cardiovascular mortality. Surgery is the treatment of choice. Growth hormone secretion is reduced by octreotide and other somatostatin analogues and to a lesser degree by bromocriptine (see Index). 

Hypersecretion of growth hormone is treated by destroying the pituitary tumor with radiation, administering Bromocriptine (inhibits release of growth hormone from the pituitary gland), and administering Octreotide (suppresses release of the growth hormone). 

In patients with hypothyroidism caused by hypothalamic or pituitary failure, alleviation of the chnical syndrome and restoration of serum T4 to the normal range are the only criteria available for estimating the appropriate replacement dose of levothyroxine. Concurrent use of dopamine, dopaminergic agents (bromocriptine), somatostatin or somatostatin analogs (octreotide), and corticosteroids suppresses TSH concentrations and may confound the interpretation of this monitoring parameter. ... 

Neuromodulatory agents include cyproheptadine, bromocriptine, valproic acid, ritanserin, and octreotide. None of the neuromodulatory agents has demonstrated consistent clinical efficacy in the treatment of Cushing s disease. The existence of a bromocriptine-responsive subset of patients remains controversial. ... 

Flogstad AK, Halse J, Grass P, et al. A comparison of octreotide, bromocriptine, or a combination of both drugs in acromegaly. J Clin Endocrinol Metab 1994 79 461 65. 

Octreotide acetate is an endocrine and metabolic agent, whose actions mimic those of natural hormone somatostatin. It suppresses secretion of serotonin and gastroentero-pancreatic peptides (e.g., gastrin, insulin, glucagon, secretin, and motilin), and also suppresses the growth hormone. It is indicated in the symptomatic treatment of diarrhea associated with carcinoid tumors, treatment of profuse watery diarrhea associated with vasoactive intestinal peptide tumors (VIPoma), and to reduce blood levels of growth hormone and IGF-1 in acromegaly patients who have had inadequate response to or cannot be treated with resection, pituitary irradiation, and bromocriptine at maximally tolerated doses. 

Octreotide modestly increases the bioavailability of bromocriptine, whereas bromocriptine does not appear to alter octreotide pharmacokinetics. 

The combined use of bromocriptine 5 mg twice daily and subcutaneous octreotide 200 mierograms twiee daily increased the bioavailability of bromocriptine by about 40%, without altering its elearance or half-life. The pharmaeokinetics of octreotide were unchanged. This effect may contribute to the increased effieaey of eombined treatment in acromegaly shown in some studies. Bear it in mind when considering eombined ther-apy. 

Anderson, E., Ferguson, J.E., Morten, H., Shalet, S.M., Robinson, E.L. and Howell, A. (1993) Serum immunoreactive and bioactive lactogenic hormones in advanced breast cancer patients treated with bromocriptine and octreotide. Eur. ]. Cancer., 29A, 209-217. 

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