Do I need a medical or counseling degree?
In the United States, hypnotherapy is an unregulated profession (some would say it is a self-regulated profession), meaning you do not require a license to offer, provide and charge for hypnotherapy services.
There are a few states that have specific laws about hypnotherapy, mostly to keep it clearly different from psychotherapy and medical practice for the sake of clarity for consumers. If you are going to be doing business in Colorado, Connecticut, Indiana, or Washington, you will need to be make sure you register with the state. If you will be doing business in California, Florida, Hawaii, Illinois, New Jersey, or Utah, be sure to check and follow local and state requirements.
You do not need any other degree or medical certification to be a professional hypnotherapist. If you have a degree or professional experience in the medical, counseling or other industry, then it can only help you. Many medical, counseling and therapy professionals choose to augment their practices with hypnotherapy. Since hypnotherapy schools in many states offer hours that count toward the required continuing education hours in the medical industry, hypnotherapy is a great compliment in the learning as well as the practice.
It is important that you do not practice any kind of medicine, diagnose any kind of illness or condition, nor prescribe any kind of substance to clients unless you are a state-licensed medical professional, like a doctor. If you don't have a PhD and a state medical license, you can certainly still make a good living as a hypnotherapist; just don't diagnose or practice medicine in any way. In some states (e.g., California), touching a client qualifies as massage, which does require a license. Check your state laws to know more.