Got tired of popping aspirin every day, so I decided to try this on my sore elbow. Amazingly, it has helped a lot. Best as I can explain it, the little vibration and zaps from the pen head (in particular the round head attachment) relaxed the tissue for a while. I use the pen once in the morning and once at night, that is enough to bring me significant pain relief. If you suffer any kind of similar condition, I highly recommend this to you!