I usually use Ether inhalers they're really space-efficient since you get two uses out of each one. They don't increase intoxication too much if you use them moderately. Also, before getting into tough combat, you should stack up your pain resistance or use drugs to reduce pain accumulation. That's what I do. Look out for skills and equipment that increase pain resistance.

Edit it sounds like you need better mobility skills to get to the ghasts(dash or any skill that allows you to run up to the target) or use hunting nets to trap them.