A dopamine agonist medication that binds selectively with D1 and D2 dopamine receptors in the substantia nigra and the nigrostri-atal fibers (areas of the brain integral to movement) to simulate dopamine action. Pergolide is commonly taken as either one of the adjunct therapies employed to enhance the effectiveness of levopoda; or as monotherapy in early Parkinson’s disease when symptoms are minor to moderate. Because it is an ergot-derived medication, it has an effect on blood vessels as well. Although the most common consequence of its use is orthosta-tic hypotension (a drop in blood pressure with a change in position), a sudden surge in blood pressure also can occur. Other side effects include daytime somnolence, hallucinations, headache, nausea, and changes in personality or mood. Unlike other agonists, pergolide’s ergot derivation also puts it at risk of causing scarring (fibrosis) of the lungs, the covering of the heart, or the so-called retroperitoneal tissues and organs in the back of the abdomen. Pergolide usually is titrated to a therapeutic dosage to minimize side effects, and the person takes increasingly larger dosages over several weeks. It should be discontinued in similar fashion, in decreasing dosages over several weeks. Women who are pregnant or trying to become pregnant should not take pergolide or other ergot alkaloids, as ergot affects reproductive hormones.