The Role of Paracetamol (acetaminophen) in the Reduction of Tremor in Parkinson’s Disease – a Case Study

Parkinson’s disease (PD) affects millions of people.  Tremor is a common symptom. Treatment with levodopa can reduce tremor but is associated with “off periods” when the tremor returns as the dose wear off. The association of levodopa with neurotoxicity needs to be managed. This case study demonstrates the potential role of paracetamol (acetaminophen) in reducing tremor by extending the duration of levodopa efficacy. The case study aimed to confirm visual observations of tremor reduction associated with paracetamol medication. It utilised a mobile phone accelerometer and a software application to monitor the tremor of a subject with PD. The data produced provided information on frequency and variations in the intensity of the tremor.  It was found that paracetamol alone does not appear to be effective at reducing tremor. The results show that paracetamol can reduce tremor in subjects during the period when their levodopa dose is usually wearing off particularly in the case of tremor concurrent with arm pain. There have been previous reports of a role for paracetamol or more particularly one of its metabolites, N-acetyl-p-benzoquinonimine, (NAPQI) in inhibiting pain signals in the spinal column. This could partly explain the theoretical basis for the reduction in tremor in this case.