#hypnagogue  an agent that induces drowsiness or sleep
  supertype:  agent.causal_agent  a substance that exerts some force or effect
  subtype:  soporific__hypnotic  a drug that induces sleep
     subtype:  narcoleptic  a soporific drug that produces an uncontrollable desire to sleep
     subtype:  sleeping_pill__sleeping_tablet__sleeping_capsule__sleeping_draught  a soporific drug in the form of a pill (or tablet or capsule)

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