Hydra

 is a consumable item in Fallout: New Vegas.

Characteristics
Hydra is similar to a Doctor's Bag in that it restores limb damage, however Hydra slowly restores damage over time unlike the Doctor's Bag, which takes effect immediately. It also heals all limbs at once. In hardcore mode, Hydra is superior to the Doctor's Bag, which only partially heals a single damaged limb, or heals all limbs for a tiny amount.

This item is crafted over a campfire. You will need 75 Survival skill, Cave fungus (5), Night Stalker Blood (3), and Radscorpion Poison Gland (2). Cave fungus is extremely rare, and even finding enough to use this recipe once in an entire playthrough is unlikely unless you are thorough about looting Caesar's troops, who have a rare chance of having one.

It requires 75 survival skill to be crafted, otherwise it can occasionally be found in first aid boxes or bought from chem vendors. You can teach Jack to make it if you have enough skill, but he is the only vendor who routinely stocks it.

The player character can become addicted to Hydra.