Apply the UK Brain Bank criteria before labeling parkinsonism, and confirm the PD diagnosis only when asymmetric cardinal features, a positive levodopa response, and absence of red flags are documented together. Consider skin biopsy for alpha-synuclein when the clinical picture is equivocal.

Alpha-synuclein skin biopsy is an emerging diagnostic tool; Newer options include inhaled or sublingual formulations of levodopa, as well as apomorphine, which can be given as a sublingual rescue therapy or an injection; Impaired postural reflexes are also common, alongside systemic problems like constipation, orthostatic hypotension, depression, and sleep disruptions; Also look at the broader clinical picture, including autonomic function, cognitive changes, and any swallowing difficulties; Relies on identifying at least two out of three cardinal features: bradykinesia, a resting tremor, and rigidity, though postural instability is often considered as well