Serums are the liquids used to induce illusions known as simulations. They are either taken orally or injected into the body through a syringe. They are clearish liquids that occasionally have a slight tint to them. Divergents are not affected by most of the serums and they remain aware that they are in a simulation. Serums can be injected individually or airborne. Most factions have a serum for their own uses.
- Fear Serum - Dauntless (Fear)
- Truth Serum - Candor (Truth)
- Peace Serum - Amity (Peace)
- Death serum - Erudite (Death)
- Memory Serum - Abnegation (Memory)
- Paralytic serum - Paralytic (movement)
- Eventually Tris Prior refuses to let anyone inject her with a serum but herself because she cannot trust anyone.