As I understand it, ZClassic scripting does not yet include scripts to take items away. I suggest there should be commands to give and take items from the player. I also suggest there should be a way to save multiple snapshots of which items a player has collected at a particular point.
This would allow the player to switch between different characters (young link and old link, for example) and play in the same world, collecting items that can only be used by one or the other character.
Alternatively, this could be accomplished by a script that "de-activates" an item in the player's possession on any screen or dmap, until another script "re-activates" it. This script would have to be able to handle de-activating an item the player doesn't yet possess.