Poison pill

Poison pill may refer to:
 * Suicide pill, a physical pill for suicide by poison
 * Poison pill amendment or wrecking amendment, an addition to a legislative bill that renders it ineffective
 * Shareholder rights plan, also called a poison pill, a subclass of anti-takeover provisions that dilutes the attacker's power
 * Poison pill (NBA), a type of player contract provision for some free agents in the National Basketball Association
 * Poison pill (NFL), a type of player contract provision for some free agents in the National Football League from 1996 to 2010