Ergot derivatives Cabergoline

Dopamine receptor agonists. Deficient dopaminergic transmission in the striatum can be compensated by ergot derivatives (bromocriptine p. 114], lisu-ride, cabergoline, and pergolide) and nonergot compounds (ropinirole, prami-pexole). These agonists stimulate dopamine receptors (D2, D3, and D sub-types), have lower clinical efficacy than levodopa, and share its main adverse effects. 

At least as effective as bromocriptine in the treatment of advanced parkinsonian patients with levodopa-related motor fluctuations adverse effects similar in incidence and severity appears to lack some of the toxicity seen with bromocriptine, pergolide, and cabergoline (e.g., pleuropulmonary disease) may be a useful alternative in patients with intolerable adverse effects due to ergot derivatives... 

Cabergoline Another ergot derivative with similar effects ... 

F. Prolactin-Inhibiting Hormone (PIH, Dopamine) Dopamine is the physiologic inhibitor of prolactin release. Because of its peripheral effects and the need for parenteral administration, dopamine is not useful in the control of hyperprolactinemia, but bromocriptine and other orally active ergot derivatives (eg, cabergoline. pergolide) are effective in reducing prolactin secretion from the normal gland as well as from pituitary tumors. 

Because cabei oline is an ei ot derivative, the manufacturers have looked at what happens if other ergot derivatives are used concurrently, but have so far found no evidence of changes in the efficacy or safety of cabergoline. Nevertheless they do not recommend their concurrent use. Similarly, the manufacturers of bromocriptine do not recommend concurrent use of other ergot derivatives. ... 

Cabergoline is an ergot derivative that is metabolised by the eytochrome P450 isoenzyme CYP3A4 (see also Bromoeriptine and other dopamine agonists + Macrolides , p.678). Itraeonazole is a potent inhibitor of this isoenzyme, and would therefore be expected to inerease cabergoline levels. 

The ergot alkaloids are variably absorbed from the gastrointestinal tract. The oral dose of ergotamine is about ten 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 the amine derivative cabergoline are well absorbed from the gastrointestinal tract. 

Dopamine receptor agonists. Striatal dopamine deficiency can be compensated by lysergic acid derivatives such as bromocriptine (p.116), lisuride, cabergoline, and pergolide and by the non-ergot compounds ropinirole and pramipexole. 

Bromocriptine, pergolide, cabergoline Inhibit prolactin release Stop lactation inhibit growth of pituitary tumors Ergot alkaloid derivatives with potent dopamine agonist activity... 

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