Someone recently asked which career would be better, one in pharmaceutical sales or medical device sales. They are different even though both are in the health care field. Both areas can involve physicians as customers but for medical devices, the customer base would involve more than just doctors and more types of individuals than compared to pharmaceutical sales. The salary structure is also different.
To get the best answer, it is best for somebody who is interested in these careers to speak to reps who are already working in these fields. Even shadow them for a day at work if possible to get an idea of what their jobs are like. This will give you a true accurate view of whether you would like these careers or not.
For pharmaceuticals, different areas within drug sales are in an article about Pharmaceutical Sales Jobs.