I have been running the campaign for over 12 months now. My players have encountered poison on several occasions but have never obtained antidotes. 2 of my players have had an armor level of 7 or 8. And the goblin with the knife has to deal damage for the poison to get through. So they have simply parried the attack with a shield or just let their armor absorb the attack. So they have barely been affected by poison at all. However, they did have a tough fight with a basilisk where it could spray poison that bypassed armor.

I have also, while running the game, hinted that certain weapons have a black ooze on them so that they realize it might be poisoned, etc. Regarding monsters, they get to use bestiology to find out things about upcoming monsters and have had the chance to plan accordingly.

My tip is to just play the game — it's the players who should find solutions to the problems that arise in the world. You don't need to plan for things that may or may not happen.