Hyperprolactinemia dopamine agonists

Dopamine agonists are the first-line treatment of choice for all patients with hyperprolactinemia transsphenoidal surgery and radiation therapy are reserved for patients who are resistant to or severely intolerant of pharmacologic therapy. 

Most women with hyperprolactinemia require dopamine agonist therapy to achieve regular ovulatory cycles and pregnancy. Since restoration of the ovulatory cycle may occur within 1 week of initiating therapy, caution patients regarding their potential to become pregnant.51... 

If hyperprolactinemia is identified as the cause of amenorrhea, the use of bromocriptine, a dopamine agonist, results in a reduction in prolactin concentrations and the resumption of menses. 

Dopamine Dopamine agonists used for treatment of hyperprolactinemia... 

No preparation of prolactin is available for use in prolactin-deficient patients. For patients with symptomatic hyperprolactinemia, inhibition of prolactin secretion can be achieved with dopamine agonists, which act in the pituitary to inhibit prolactin release. 

Dopamine agonists suppress prolactin release very effectively in patients with hyperprolactinemia. GH release is reduced in patients with acromegaly, although not as effectively. Cabergoline and bromocriptine are also used in Parkinson s disease to improve motor function and reduce levodopa requirements (see Chapter 28). Newer, nonergot D2 agonists... 

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. 

Bankowski BJ, Zacur HA Dopamine agonist therapy for hyperprolactinemia. Clin Obstet Gynecol 2003 46 349. [PMID 12808385]... 

Tollin SR. Use of the dopamine agonists bromocriptine and cabergoline in the management of risperidone-induced hyperprolactinemia in patients with psychotic disorders. J Endocrinol Invest 2000 23(ll) 765-70. 

Dopamine agonists are useful for treating problems induced by hyperprolactinemia amenorrhea, galactorrhea, breast tenderness (mastodynia), infertility, and hypogonadism. 

The neurotransmitter dopamine has currently found clinical application in the treatment of cardiovascular collapse and shock. Treatment with dopamine-related drugs has been limited to such brain disorders as Parkinson s disease, schizophrenia, and hyperprolactinemias. Accumulating data from animal experiments, however, indicate the possible involvement of dopamine in other diseases and the potential use of dopamine agonists or antagonists in these disorders. Gastrointestinal disturbances (especially duodenal ulcer disease) seem to represent such a group of dopamine-sensitive alterations. 

Dopamine inhibits prolactin synthesis. Drugs that inhibit dopamine synthesis or activity (e.g. antihypertensives, antidepressants, estrogen, phenothiazines, opiates), are the most common cause of hyperprolactinemia. Prolactin-secreting pituitary tumors sometimes are treated with bromocriptine, a dopamine agonist. 

Other dopamine agonists that have been used in the treatment of hyperprolactinemia but are not commercially available in the United States include lisuride, terguride, metergoline, dihydroergocristine. 

Hyperprolactinemia is a common disorder that can have a significant impact on fertility. Hyperprolactinemia is most commonly caused by the presence of prolactin-secreting pituitary tumors and various medications that antagonize dopamine or increase the secretion of prolactin. Available treatment options for this disorder include medical therapy with dopamine agonists, radiation therapy, and transsphenoidal surgery. In most cases, medical therapy with dopamine agonists... 

Ergot derivative prototype dopamine agonist in CNS inhibits prolactin release. Alternative drug in parkinsonism and hyperprolactinemia. Tox CNS, dyskinesias, hypotension. 

Valassi E, Klibanski A, Biller BM. Potential cardiac valve effects of dopamine agonists in hyperprolactinemia. J Clin Endocrinol Metab 2010 95(3) 1025-33. 

Another study evaluated whether the long-term use of ergot-derived dopamine agonists for hyperprolactinemia may be associated with increased risk of significant valvular heart disease. A total of 74 patients (mean age 48 1.4 years, 23% male) with prolactinoma treated with the drugs for at least lyear were evaluated with... 

The answer is b. (Hardman, pp 282—283J Central dopamine receptors are divided into Dt and D2 receptors. Antipsychotic activity is better correlated to blockade of D2 receptors. Haloperidol, a potent antipsychotic, selectively antagonizes at Dz receptors. Phenothiazine derivatives, such as chlorpromazine, fluphenazine, and promethazine, are not selective for D2 receptors. Bromocriptine, a selective D2 agonist, is useful in the treatment of parkinsonism and hyperprolactinemia. It produces fewer adverse reactions than do nonselective dopamine receptor agonists... 

Bromocriptine (Parl el) [Antiparkinsonian Agent/Dopamine Receptor Agonist] Uses Parkin on Dz, hyperprolactinemia, acromegaly, pituitary tumors Action Direct-acting on the striatal dopamine receptors X prolactin secretion Dose Initial, 1.25 mg PO bid titrate to effect, w/ food Caution [B, ] Contra Severe ischemic heart Dz or PVD Disp Tabs, caps SE X BP, Raynaud phenomenon (vasospastic disorder resulting in discoloration of the fmgers/toes), dizziness, N, hallucinations Interactions T Effects W/ erythromycin, fluvoxamine, nefazodone, sympathomimetics, antihypertensives X effects W/ phenothiazines, antipsychotics EMS Monitor BP may cause intolerance to EtOH OD May cause NA, severe hypotension give IV fluids symptomatic and supportive... 

Five patients (four women and one man, aged 30-45 years), who were evaluated for risperidone-induced hyperprolactinemia, had significant hyperprolactinemia, with prolactin concentrations of 66-209 pig/1 (1017). All but one had manifestations of hypogonadism, and in these four patients, risperidone was continued and a dopamine receptor agonist (bromocriptine or cabergoline) was added in three patients this reduced the prolactin concentration and alleviated the hypogonadism. 

Mesulergine is an 8-alpha-aminoergoline derivative that acts as a dopamine receptor agonist. In a blind, crossover study in six patients with hyperprolactinemia, mesulergine 0.5 mg caused fewer adverse effects than bromocriptine 2.5 mg, while the prolactin release-inhibitory effect of the two was of the same order (1). 

Indications Hyperprolactinemia, parkinsonism Category Dopamine receptor agonist Half-life 63-69 hours... 

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