Take a depressed person who wants to commit suicide, but is too depressed to do it. Put thing on an anti-depressant that raises their mood and improves them over the course of a few weeks. There risk for a period in there where a patient has not exited self-harm territory, but now has energy to do things - including self-harm.

The drug isn't causing suicide. It's just unfortunately taking a patient through a risky period.

Many people do not understand that anti-depressants don't work instantaneously. They take time. That is where the risk comes from.