diff --git a/lib/reducers/message-reducer.js b/lib/reducers/message-reducer.js
--- a/lib/reducers/message-reducer.js
+++ b/lib/reducers/message-reducer.js
@@ -26,6 +26,7 @@
   fetchMostRecentMessagesActionTypes,
   sendTextMessageActionTypes,
   sendMultimediaMessageActionTypes,
+  sendReactionMessageActionTypes,
   saveMessagesActionType,
   processMessagesActionType,
   messageStorePruneActionType,
@@ -858,6 +859,13 @@
       { [action.payload.threadID]: messageTruncationStatus.UNCHANGED },
       newThreadInfos,
     );
+  } else if (action.type === sendReactionMessageActionTypes.success) {
+    return mergeNewMessages(
+      messageStore,
+      action.payload.newMessageInfos,
+      { [action.payload.threadID]: messageTruncationStatus.UNCHANGED },
+      newThreadInfos,
+    );
   } else if (action.type === deleteEntryActionTypes.success) {
     const payload = action.payload;
     if (payload) {