If you know all the drugs listed in first aid, their mechanisms of actions, uses, and side effects, you should be fine (pass). Toxicological treatments (acetylcholinesterase inhibitors for atropine poisoning, etc) and toxic effects as well as regular drug contraindications are high yield too. I also recall quite a few questions on signal transduction, neurotransmitters and the associated autonomics, but not TOO many.
Oh, there were a lot of questions that would describe a drug and its actions, and then ask you "why does this happen" or "what is the most likely reason for this", etc. These are different from simple "mechanism of action" questions, because they're dealing with the concepts behind it. The problem is, first aid really doesn't cover a lot of this, so you'll have to pull some of it out of your memory from lecture.
But again, stick to the drugs listed in first aid, and you'll definitely pass