Psychologist:
A person that has completed their studies in psychology. They are not trained to to do therapy.
Psychotherapist FSP:
Psychotherapists with this title have a masters in psychology and a recognised 4-year psychotherapy training, that includes extensive supervision and self exploration.
Psychiatrist:
Psychiatrists are medical doctors, who are trained in medical treatment for psychiatric illnesses, not in therapy.
Psychiatrist with the additional title of psychotherapist FMH:
To acquire the additional title of psychotherapists, psychiatrists have to complete a recognised 4-year psychotherapy training that is similar to the one for psychologists but less extensive (for whatever reason ;-).
Generally I would recommend seeing a psychiatrist if you suffer from a long-term psychiatric condition such as depression or psychosis that need medical treatment. If – on the other hand – you are looking to deal with traumatic experiences, eating disorders, social anxiety, self-esteem issues, relationship issues etc., I would recommend seeing a psychologist/psychotherapist or a psychiatrist/psychotherapist.
Psychologist/psychotherapists are not allowed to prescribe medicine.
I hope this clarifies the confusion a little bit.
Good luck.
Dorothe (myself a psychotherapist FSP)