In rare instances, teeth grinding can be a side-effect of antidepressant medicines.

CNN: What can I do about teeth grinding?

An amazing recent example of this comes from a study that found that when a depressed mother takes an antidepressant medication and responds, the effect on depressive symptoms is bigger in her kids than it is in her.

CNN: What can cause depression in a 12-year-old?

In the case of depression, says Dr Kirsch, giving patients placebo pills can produce very nearly the same effect as dosing them with the latest antidepressant medicines.

ECONOMIST: Alternative medicine: Think yourself better | The

The word antidepressant covers a wide range of medications that have very different mechanisms of action and very different side effect and risk profiles.

CNN: What are antidepressants' long-term effects?