In the U.S. military, go pills and no-go pills refer to medications meant, respectively, to increase wakefulness or to induce sleepiness in order to ensure adequate alertness or rest in preparation for upcoming tasks.
Go pill
A go pill refers to a wakefulness-promoting agent used for fatigue management, especially in a military combat-readiness context; this is contrasted with a no-go pill, which is used to promote sleep in support of combat operations. A go pill generally contains one of the following drugs:
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