List of items, what they do.

Tonic- restores 50 HP.
Mid tonic- restores 200 HP.
Full tonic- restores 500 HP. 
Ether- Restores 10 MP.
Mid Ether- Restores 30 MP.
Full ether- Restores 60 MP.
Hyper Ether- Restores all MP
Elixir- Restores all HP/MP.
MegaElixer- Restores HP/MP for all.
Heal- Recovers status.
Revive- Revives an ally.
Shelters- Restores HP/MP at save points.
Power Meal- Recover from Ò?Ó.
Lapis- Restore 200 HP for all.
Barrier- Ups Mg. def.
Shield- Ups Phys. Def.