Yesterday, i've reached Blood-starved Beast and i ended up using all the antidotes my character have. Then when i died the game didn't retrieve the antidotes from the storage box as it does for quick silver bullets and blood vials. So i went back to hunters dream and checked the storage box but it is only used for storing the items that my character have and i can't see the stored items.

Can anyone tell me how this mechanic works ?

You need to press R2 or L2 to switch between your character held items and your storage.

It should, however, automatically restock your character out of your storage upon death, or returning to Hunters Dream. So you must be out of Antidotes.

@zevvion: I thought that this is the case but when i went to the bath messenger to buy some antidotes the stored items were 10. So i went to the storage box and stored two antidotes and went then to Old Yhanarm but the game didn't restock my character. Then i jumped off to kill my character and nothing.

Anyway thanks for the tip cause it will save me from needless farming.

That's odd. My antidotes refill automatically. Perhaps because you stored them manually they don't add automatically? Unlikely though.