An open-label pilot study with high-dose thiamine in Parkinson's disease
The administration of high doses of thiamine to patients with PD was effective in reversing the parkinsonian symptoms; we then suppose that the parenteral thiamine supplementation may play an important role in restoring the survivor neurons and in limiting the disease progression, and that the dysfunction of the thiamine-dependent processes could be a primary pathogenic pathway leading to the death of dopaminergic and non-dopaminergic neurons in PD. The thiamine-dependent processes are impaired in the cerebral tissues of patients with several neurodegenerative diseases and the activity reduction of the thiamine-dependent enzymes can be readily linked to the symptomatology and the pathology of the disorders. Most neurodegenerative diseases share then similarities and could be responsive to high doses of thiamine (Butterworth, 2003; Jhala and Hazell, 2011; Lu’o’ng and Nguyên, 2012; Costantini et al., 2015; Mkrtchyan et al., 2015).
In conclusion, we found that the long-term treatment with the intramuscular administration of thiamine has led to a significant improvement of motor and non-motor symptoms of the patients with PD; this improvement was stable during time and without side effects.