Rotigotine, a member of the dopamine agonist class of drugs, is delivered continuously through the skin (transdermal) using a silicone-based patch that is replaced every 24 hours. A dopamine agonist works by activating dopamine receptors in the body, mimicking the effect of the neurotransmitter dopamine. The precise mechanism of action of rotigotine as a treatment for Restless Legs Syndrome is unknown but is thought to be related to its ability to stimulate dopamine
There is no indication of a QT/QTc prolonging effect of Neupro in doses up to 24 mg/24 hours. The effects of Neupro at doses up to 24 mg/24 hours (supratherapeutic doses) on the QT/QTc interval was evaluated in a double-blind, randomized, placebo- and positive-controlled (moxifloxacin 400 mg IV, single dose) parallel-group trial with an overall treatment period of 52 days in male and female patients with advanced-stage Parkinson's disease. Assay sensitivity was confirmed by significant QTc prolongation by moxifloxacin.
The most likely symptoms of overdose would be those related to the pharmacodynamic profile of a dopamine agonist, including nausea, vomiting, hypotension, involuntary movements, hallucinations, confusion, convulsions, and other signs of excessive dopaminergic stimulation.