Using the device multiple times a day is not harmful, but will not yield intensified or expedited results. Misuse and Overuse of the device can also result in you having to charge the device more frequently and potentially shorten the lifespan of the device. The device was clinically tested and designed to yield maximum results in 1 daily 3-minute session. Remember - consistency is key to getting the best results possible and using the device every day for 3 minutes will deliver the best results.