Bromocriptine, originally marketed as Parlodel and subsequently under many brand names, is an ergoline derivative and dopamine agonist that is used in the treatment of pituitary tumors, Parkinsons disease, hyperprolactinaemia, neuroleptic malignant syndrome, and, as an adjunct, type 2 diabetes. It was patented in 1968 and approved for medical use in 1975. Medical uses
Bromocriptine is used to treat acromegaly and conditions associated with hyperprolactinemia like amenorrhea, infertility, hypogonadism, and prolactin-secreting adenomas. It is also used to prevent ovarian hyperstimulation syndrome and to treat Parkinsons disease.Since the late 1980s it has been used, off-label, to reduce the symptoms of cocaine withdrawal but the evidence for this use is poor.A quick-release formulation of bromocriptine, Cycloset, is also used to treat type 2 diabetes. When administered within 2 hours of awakening, it increases hypothalamic dopamine level and as a result decreases hepatic glucose production. It therefore acts as an adjunct to diet and exercise to improve glycemic control. Side effects
Most frequent side effects are nausea, orthostatic hypotension, headaches, and vomiting through stimulation of the brainstem vomiting centre. Vasospasms with serious consequences such as myocardial infarction and stroke that have been reported in  connection with the puerperium, appear to be extremely rare events. Peripheral vasospasm (of the fingers or toes) can cause Raynauds Phenomenon. Bromocriptine use has been anecdotally associated with causing or worsening psychotic symptoms (its mechanism is in opposition of most antipsychotics, whose mechanisms generally block dopamine receptors).
It also interacts with other dopamine receptors and with various serotonin and adrenergic receptors. Bromocriptine has additionally been found to inhibit the release of glutamate by reversing the GLT1 glutamate transporter.As an antagonist of the serotonin 5-HT2B receptor, bromocriptine has not been associated with cardiac valvulopathy. This is in contrast to other ergolines acting instead as 5-HT2B receptor agonists such as cabergoline and pergolide but is similar to lisuride which likewise acts as a 5-HT2B receptor antagonist. Chemistry
Like all ergopeptides, bromocriptine is a cyclol; two peptide groups of its tripeptide moiety are crosslinked, forming the >N-C(OH)< juncture between the two rings with the amide functionality. Bromocriptine is a semisynthetic derivative of a natural ergot alkaloid, ergocryptine (a derivative of lysergic acid), which is synthesized by bromination of ergocryptine using N-bromosuccinimide. History
Bromocriptine was discovered by scientists at Sandoz in 1965 and was first published in 1968; it was first marketed under the brand name Parlodel.A quick-release formulation of bromocriptine was approved by the FDA in 2009.