Small Health is a fairly weak health item in the Serious Sam games. In every game it appears it, it gives the player 10 health points.
Its looks vary depending on the game. In Serious Sam 1, Serious Sam HD, Serious Sam: Next Encounter and Serious Sam: Double D, it is a floating test tube of purple liquid. In Serious Sam 2, it is a floating pill with a semi-transparent red top and a semi-transparent white bottom. On each side is a + on it. In Serious Sam 3: BFE, it is two small first aid packs together.
In Serious Sam 3: BFE and Serious Sam: Double D, it is often found between hordes of weak enemies or small amounts of enemies to that the player can recover some health they might've lost from weak enemies.