In contrast to other treatments such as (stem) cell treatment or gene therapies the side-effects have been well studied for a long time in a huge number of patients. The result is that no ill effects occur.
In fact, shock waves are in daily clinical use for the treatment of numerous conditions especially in orthopedics and traumatology. These include tendinitis like tennis elbow or bone non-unions and wound healing disorders.
These are also clinical applications being tested for erectile dysfunction and ischemic heart disease as well as spine injuries.