Medical devices and method for making and using medical devices are disclosed. An example method for treating a blood vessel may include disposing a medical device within the blood vessel at a position adjacent to a lesion. The medical device may include an elongate shaft having a distal end region, a balloon coupled to the distal end region, and a cavitation member disposed within the balloon. The method may also include inflating the balloon to a first pressure, activating the cavitation member, and inflating the balloon to a second pressure greater than the first pressure.