You are likely to be asked about general classes of psychiatric medications. Generally speaking, antidepressants show no effects for 7-10 days and don't reach full therapeutic levels for 4-6 weeks. You may also be asked about extrapyramidal symptoms (EPS), which occur with certain mental health medications (chiefly antipsychotics). This is manifested in shuffling gait, feelings of restlessness, involuntary movement of facial muscles, etc.
Situation questions are always popular, particularly ones about escalating patients. The most important things are to keep a calm demeanor, speak softly and slowly, and remove yourself from the situation if you see that you are not being effective (rank has no meaning in these situations - a CNA who has a rapport with the patient may be more effective at deescalating the situation than a licensed nurse).
Congrats! It's a challenging field of nursing. Be ready for all kinds of abuse...and not just from patients but from coworkers, management too. I wish that weren't the case but it is in our hospital. The economy is bad so you have to put up with it unfortunately. We have great benefits though and the pay is excellent so through the bruises and broken bones at least one can pay his/her bills!!
Be as positive as you can. Follow all policies and procedures to the "t". Best of luck!