Hypnosis and Hypnotherapy are perfectly safe!
The answer is "no and possibly". There have been clandestine uses of hypnosis, e.g. some intelligence organisations have been known to engage in unethical uses. However, in a clinical and professional sense, it is entirely safe and can make some profound changes to people with many life-limiting conditions. Many of the conditions that hypnosis helps are the result of dysfunctional sensory responses to emotional and cognitive misperceptions, While the subconscious intent of some of these emotional responses is ostensibly positive, e.g. fear of needles, the resultant phobia feels anything but positive! The downside, though, might be more harmful because the content of the syringe may save your life! The emotional brain lacks the ability or desire to rationalise the ups and downs of needles, they equal danger and danger is a no go area; period!
In some sense hypnosis occurs in the negative, i.e. in trance states, we can develop unwanted behaviours, again citing the fear of needles. The fear may simply have developed in response to observing someone else reacting to a painful injection. It could also be conscious, perhaps as a result of knowing someone contracting an awful disease through using an infected syringe (HIV?). Or, even an ordinarily safe routine or procedure like a blood transfusion. In these instances, learning occurs both consciously and subconsciously and is then consolidated into a fear response during our ordinary nighttime sleep. Hypnotic learning, in terms of the solution, occurs at the subconscious level of memory (not mind) and is therefore out of the reach of our conscious awareness. Basically, this is because our conscious states often do more to exacerbate our issues, than they do to fix them! So, to a certain degree, we are sometimes using hypnosis to de-hypnotize the client?
It is often cited by therapists, relative to hypnosis, you cannot be made to do anything against your will. But what will is it, conscious or subconscious?? In any event, this is not true but let me explain why! If you're a smoker or someone who eats emotionally, the subconscious elements of your brain want to smoke and it just loves cream cakes and french fries! This part of you wants to maintain its agenda, which is obviously not good for you but you do it anyway. So, if you already know all there is to know, e.g. smoking will kill you and obesity makes you unhealthy, stopping those behaviours should be easy, right? Obviously you know the answer is no. But what is interesting is this. You know that something you are doing is bad for you, yet you continue to do it. That means, at some level you want to do it, correct? So, if part of you wants to and part of you doesn't, I have to be able to get the part of you that wants to do it, to stop. Therefore, I have to get you to do something against your will. Of course, the message about not being coerced to do anything against your will is just one of many iterations taught in hypnotherapy training schools. The intention, I believe, is honourable but it flys in the face of the reality and it is incongruent with many other things that are said of hypnosis!
So, in answer to the question, if you are looking for a safe, natural and effective way to overcome a challenging life issue; I would highly recommend hypnotherapy. It is safe, in the right hands!