Causes of secondary parkinsonism

The symptoms of parkinsonism can be caused by a wide range of conditions, including infections; exposure to toxic chemicals; drug side effects; brain tumours; repeated head trauma; and metabolic disorders.¹ ‘Secondary parkinsonism’ is caused by something other than truly ‘idiopathic’ PD.¹ Accurate diagnosis of such cases is therefore critical to provide the correct treatment and prognosis for the patient.¹

Drug-induced parkinsonism can often be reversed simply by identifying and withdrawing the drug responsible.⁴ Drugs leading to secondary parkinsonism include certain antipsychotic medications and antiemetics (to reduce nausea or vomiting).⁴

References:
1.Tolosa E, Wenning G, Poewe W. The diagnosis of Parkinson’s disease. Lancet Neurol 2006; 5 (1): 75–86.

2.Jang H, Boltz DA, Webster RG, Smeyne RJ. Viral parkinsonism. Biochim Biophys Acta 2009; 1792 (7): 714–721.

3.Çoban A, Küçükali CFI, Bilgiç B, et al. Evaluation of incidence and clinical features of antibody-associated autoimmune encephalitis mimicking dementia. Behav Neurol 2014; 2014: 935379.

4.DeMaagd G, Philip A. Parkinson’s disease and its management. Pharmacol Therapeut 2015; 40 (8): 504–510.