Parkinson’s disease and tardive dyskinesia (TD) are two distinct neurological conditions that can exhibit overlapping symptoms, which can sometimes make it challenging to differentiate between them, especially when assessing individuals who have been suffering from the disease for a long time. It is not necessary for all known and common symptoms of the condition to overlap. However, there are glaring differences in terms of severity and how these problems can develop, affecting individuals.

Tremors
One of the most recognizable symptoms of Parkinson’s disease and Tardive dyskinesia is early tremors. Resting tremors are a typical feature of Parkinson’s disease, affecting a majority of the patients. These tremors generally develop in the arms and legs. Second, if there is any activity, the tremors decrease or stop during purposeful movement. This means Parkinson’s tremors are typically rhythmic and worsen when the person is sitting or lying down. The tremors may initially be subtle, like a slight shaking of the hand, but can become more pronounced over time. Tardive dyskinesia also involves tremors that may more or less resemble the resting tremors observed in PD. However, TD tremors can be more irregular and jerkier, more prolonged, and visibly evident when compared to the subtle movements of Parkinson’s. A thorough diagnosis will be necessary to confirm the underlying trigger of such tremors.

Involuntary movements
While Parkinson’s primarily presents with bradykinesia (slowness of movement), it can also involve involuntary movements called dyskinesia. These movements are typically observed as sudden writhing or twisting motions of the limbs, the trunk, or even the face. TD mainly involves involuntary and repetitive movements of the face and mouth, among other affected body parts. These movements can sometimes resemble the dyskinesia symptoms seen in advanced stages of Parkinson’s disease. However, there are glaring differences that one cannot simply overlook. One of the characteristic signs of TD is the presence of involuntary facial movements.