The first effective drugs for Parkinson's disease (PD) were anticholinergics, introduced at the end of 19.th century by Charcot. Since the introduction of levodopa in the sixties of the previous century, many new drugs have emerged for the treatment of Parkinson's disease: dopamine agonists (ergot as well as non-ergot, bromocriptine, pergolide, mirapexine, ropinirole), MAO B inhibitors (selegiline, rasagiline), amantadine, COMT inhibitors (entacapone, tolcapone). In all stages of the disease, levodopa remains the most effective drug for improving motor symptoms in PD. However, long term treatment with levodopa is accompanied by the development of motor fluctuations, dyskinesia, cognitive and neuropsychiatric adverse effects and increasingly diverse spectrum of drugs is needed to alleviate motor and nonmotor symptoms. Some of these drugs have caused considerable concern and controversies and were regarded at certain points as the 'bad guys' of Parkinson's disease pharmacological armamentarium. In the article, a short review of 'bad guys' including anticholinergics, selegiline, tolcapone and dopamine agonists, is given.