A drug deactivation system according to some embodiments includes at least one degradable capsule exposed to at least one drug-retaining region of a drug delivery device and an agent. The agent is configured to render a drug ineffective upon degradation of the at least one capsule. The at least one drug-retaining region is configured to retain one of the drug and the agent and the at least one capsule is configured to retain the other of the drug and the agent.
