Pharmacotherapeutic group: prolactine inhibitors, cabergoline.
ATCvet code: QG02CB03
Pharmacodynamic properties
Cabergoline is an ergoline derivative. It has dopaminergic activity which leads to inhibition of prolactin secretion by the anterior pituitary. The mechanism of action of cabergoline was studied in in vitro and in vivo models. The most important details are outlined below:
- Cabergoline inhibits prolactin secretion by the pituitary gland and inhibits all prolactin dependent processes, such as lactation. Maximum inhibition is achieved after 4-8 hours and lasts several days depending on the administered dose.
- Cabergoline has no other effects on the endocrine system besides the inhibition of prolactin secretion.
- Cabergoline is a dopamine agonist in the central nervous system by selective interaction with the dopaminergic D2 receptors.
- Cabergoline has affinity for the noradrenergic receptors, however, this does not cause interference with the noradrenalin and serotonin metabolism.
- Cabergoline is an emetic, like the other ergoline derivatives (in potency comparable to bromocriptine and pergolide).
Pharmacokinetic properties
No pharmacokinetic data are available for the recommended dosing regimen in dogs and cats.
Pharmacokinetic studies in dogs were performed with a daily dose of 80 µg/kg body weight (16 times the recommended dose). Dogs were treated for 30 days; pharmacokinetic assessments made on day 1 and 28.
Absorption:
- Tmax = 1 hour on day 1 and 0.5-2 hours (mean 75 minutes) on day 28;
- Cmax ranged from 1140-3155 pg/ml (mean 2147 pg/ml) on day 1 and from 455-4217 pg/ml (mean 2336 pg/ml) on day 28;
- AUC (0-24 hours) on day 1 ranged from 3896-10216 pg.h.ml-1 (mean 7056 pg.h.ml-1) and on day 28 from 3231-19043 pg.h.ml-1 (mean 11137 pg.h.ml-1).
Elimination:
Plasma half life in dogs t½ on day 1~19 hours; t½ on day 28~10 hours.