There are some side effects that may cause discomfort.
For example, if you use the vibration feature at higher powers near your ear, you may feel dizziness, nausea, or general discomfort. That's why we recommend keeping vibration levels low when applying directly to the TMJ or anywhere else near the ear. You can use higher vibration around the head and neck muscles or farther away from the TMJ like the temples and masseter.
The heat setting may also have some side effects. For example, if you leave the highest heat setting on one spot for too long, you'll likely experience some redness and tenderness in that spot. If left for even longer there may be 1st degree burns. This is why we recommend keep heating times under 5 minutes at the highest heat setting.