No, hypnosis itself is not dangerous. On the contrary, it is a relaxing and invigorating experience. However, like any tool, be it a hammer or medicine, it can be used incorrectly, which can have negative consequences. How? The first lesson you learn when studying hypnosis is that "whatever you focus on, you strengthen". So can a well-intentioned but uneducated doctor make you focus on things that are unimportant or even upsetting? Yes. Therefore, it is important to choose your therapist carefully and to be aware that you can reject any suggestion that you do not find helpful. You are in control!