This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bromocriptine, Subject name: Pharmacology
[{'content': 'Which drug is used to suppress lactation? (Repeat) \nSelect and explain. \nA. Bromocriptine, B. Metoclopramide, C. Domperidone, D. Prolactin', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans: A (Bromocriptine) Ref: Basic & Clinical Pharmacology, Katzung 12th ed.Explanation:Dopamine agonists suppress prolactin release very effectively in patients with hyperprolactinemia.Bromocriptine and cabergoline are ergot derivatives with a high affinity for dopamine D2. receptors. Quinagoiide. a drug approved in Europe, is a non ergot agent with similarly high D: receptor affinity.ADR: Dopamine agonists can cause nausea, headache, light-headedness, orthostatic hypotension and fatigue. Psychiatric manifestations occasionally occur, even at lower doses, and may take months to resolve.Erythromelalgia occurs rarely. High dosages of ergot-derived preparations can cause cold- induced peripheral digital vasospasm. Pulmonary infiltrates have occurred with chronic high- dosage therapy.Cabergoline appears to cause nausea less often than bromocriptine. Receptor subtypesAgonistAntagonistMechanismGlutamateX-Methyl D-aspartate (NMDA)NMDA2-amino-5-phosphonovalerate DizocilpineExcitatory AMPAAMPACNQXExcitatory KainateKainic acidDomoic acid MetabotriopicACPD QuisqualateMCPGInhibitory (Presynaptic)GABAGABA -AMuscimolBicuculline PicrotoxinInhibitory GABA -BBaclofen2-hydroxy SaclofenInhibitoryDopamineD1 PhenothiazinesInhibitory D2BromocriptinePhenothiazine ButyrophenonesInhibitoryAcetylcholineMuscarinic MlMuscdrinePirenzepine AtropineExciatatory Muscarinic M2Muscarine BethanecholAtropine MethoctramineInhibitory Nicotinic. NicotineDihydro beta erythroidine Alpha- bungarotoxinExciatatory', 'role': 'assistant'}]