Cabergoline dosing

The ergot alkaloids are variably absorbed from the gastrointestinal tract. The oral dose of ergotamine is about 10 times larger than the intramuscular dose, but the speed of absorption and peak blood levels after oral administration can be improved by administration with caffeine (see below). The amine alkaloids are also absorbed from the rectum and the buccal cavity and after administration by aerosol inhaler. Absorption after intramuscular injection is slow but usually reliable. Bromocriptine and cabergoline are well absorbed from the gastrointestinal tract. 

Cabergoline reaches peak plasma levels within 2-3 hours after a 1 mg oral dose. It has a half-life of 63-69 hours. Metabolites are excreted mostly in feces. Bromocriptine is metabolized more quickly. 

The D2 agonists differ in their duration of action and, hence, their dosing interval e. g., bromocriptine 3 times daily, quinagolide once daily, and cabergoline once to twice weekly. 

Frank W, Moritz R, Becke B, Pauli R. Low dose cabergoline induced interstitial pneumonitis. Eur Respir J 1999 14(4) 968-70. 

Cabergoline is a selective D2 ergot agonist with a long half-life (70 hours) that is as effective as bromocriptine but dosed up to 4 mg once a day. It is available in the United States only as a 0.5-mg tablet (Dostinex, Pharmacia) for the treatment of hyperprolactinemia. A transdermal delivery form of the potent dopaminergic agonist... 

Cabergoline appears to be more effective than bromocriptine for the medical management of prolactinomas and offers the advantage of less-frequent dosing and decreased adverse events. 

Cabergoline is commercially available as 0.5-mg oral tablets. The initial dose of cabergoline for the treatment of hyperprolactinemia is 0.5 mg once weekly or in divided doses twice weekly. This dose may be increased by increments of 0.5 mg at 4-week intervals based on serum prolactin concentrations. The usual dose is 1 to 2 mg weekly however, doses as high as 4.5 mg weekly have been used. Recent studies have also evaluated the efficacy of a vaginal dosage form of cabergoline to reduce the adverse effects associated with oral therapy. ... 

Cabergoline is more effective than bromocriptine in suppressing prolactin secretion and it is more favorably tolerated. In addition, the long half-life of cabergoline allows for twice-weekly dosing, as compared to multiple daily dosing of bromocriptine. 

The pharmacokinetics of cabergoline did not change when a single dose of cabergoline 1 mg was taken after breakfast compared with the fasting state in a study in healthy subjects. ... 

Two patients taking cabergoline had improvements in their Parkinson s disease symptoms while taking itraconazole. In one case a 300% increase in cabergoline levels occurred, and the other patient reduced the dose of her medications without adversely affecting disease control. 

Another similar patient taking cabergoline 2 mg twice daily, selegiline, entacapone, and levodopa/carbidopa, experienced symptoms of overdose (hyperkinesia of the extremities) 3 days after starting itraconazole 200 mg twice daily. She reduced the dose of her Parkinson s medication, and had marked improvement in her usual Parkinson s symptoms, which then gradually reduced after stopping the itraconazole. This was repeated following two additional periods of itraconazole therapy. ... 

Another example of a negative study has been published [70 ]. In a cross-sectional, two-dimensional echocardiographic study in 72 patients (median age 36 years, 19 men) who took cabergohne for hyperprolactinemia and 72 controls prospectively matched for age, sex, and cardiovascular risk factors, there was no association between cabergoline treatment and valvulopathy the median cumulative dose exposure was 126 (58-258) mg. 

Observational studies Ovarian hyperstimulation syndrome is a life-threatening complication of assisted reproduction. Ovarian hyperstimulation syndrome was successfully treated in four patients with combination ganirelex 250 micrograms subcutaneously daily for two doses and cabergoline 0.5 mg/day for 7 days without complications [12 ]. 

Andreotti, C., Pianezzola, E., Persian , S., Pacciarini, M.A., Strolin Benedetti, M. and Pontiroli, A.E. (1995) Pharmacokinetics, pharmacodynamic, and tolerability of cabergoline, a prolactin-lowering drug, after administration of increasing oral doses (0.5,1.0, and 1.5 miligrams) in healthy male volunteers./. Clin. Endocrinol Metab., 80, 841-845. 

The Dutch authors of a report on patients with prolactinoma arrived at a broadly similar conclusion [106 ]. Of 78 patients, 47 were treated for up to 8 years (mean 5.2 years) with a mean cumulative dose of 363 mg. There was mild tricuspid regurgitation in 41% of cabergoline treated subjects (vs. 26% of controls), and aortic calcification in 40% (vs. 18%). However, none of these abnormalities was regarded as clinically relevant. One can therefore be reasonably confident of the safety of low-dose cabergoline in endocrine disease, but not with any complacency. 

Wakil A, Rigby AS, Clark AL, Kallvik-backa-Bennett A, Atkin SL. Low dose cabergoline for hyperprolactinaemia is not associated with clinically significant valvular heart disease. Eur J Endocrinol 2008 159(4) Rll. ... 

Bogazzi F, Buralli S, Manetti L, Raffaelli V, Cigni T, Lombardi M, Boresi F, Taddei S, Salvetti A, Martino E. Treatment with low doses of cabergoline is not associated with increased prevalence of cardiac valve regurgitation in patients with hyperprolactinaemia Int J Clin Pract 2008 62 (12) 1864-9. 

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