1. Bromocriptine—

An ergot alkaloid, bromocriptine acts as a partial agonist at dopamine D2 receptors in the brain. The drug increases the functional activity of dopamine neurotransmitter pathways, including those involved in extrapyramidal function. Pergolide is similar. Bromocriptine has been used as an individual drug, in combinations with levodopa (and with anticholinergic drugs), and in patients who are refractory to or cannot tolerate levodopa.