diff --git a/src/p_interaction.cpp b/src/p_interaction.cpp
index 66bdbe2a2..3004022e4 100644
--- a/src/p_interaction.cpp
+++ b/src/p_interaction.cpp
@@ -1511,6 +1511,10 @@ bool AActor::OkayToSwitchTarget (AActor *other)
 //
 // P_PoisonPlayer - Sets up all data concerning poisoning
 //
+// poisoner is the object directly responsible for poisoning the player,
+// such as a missile. source is the actor responsible for creating the
+// poisoner.
+//
 //==========================================================================
 
 bool P_PoisonPlayer (player_t *player, AActor *poisoner, AActor *source, int poison)
@@ -1526,7 +1530,7 @@ bool P_PoisonPlayer (player_t *player, AActor *poisoner, AActor *source, int poi
 	if (poison > 0)
 	{
 		player->poisoncount += poison;
-		player->poisoner = poisoner;
+		player->poisoner = source;
 		if (poisoner == NULL)
 		{
 			player->poisontype = player->poisonpaintype = NAME_None;