diff --git a/src/components/views/rooms/Autocomplete.js b/src/components/views/rooms/Autocomplete.js
index 95133778ba..32e568e2ba 100644
--- a/src/components/views/rooms/Autocomplete.js
+++ b/src/components/views/rooms/Autocomplete.js
@@ -64,6 +64,9 @@ export default class Autocomplete extends React.Component {
     onUpArrow(): boolean {
         let completionCount = this.countCompletions(),
             selectionOffset = (completionCount + this.state.selectionOffset - 1) % completionCount;
+        if (!completionCount) {
+            return false;
+        }
         this.setSelection(selectionOffset);
         return true;
     }
@@ -72,6 +75,9 @@ export default class Autocomplete extends React.Component {
     onDownArrow(): boolean {
         let completionCount = this.countCompletions(),
             selectionOffset = (this.state.selectionOffset + 1) % completionCount;
+        if (!completionCount) {
+            return false;
+        }
         this.setSelection(selectionOffset);
         return true;
     }
diff --git a/src/components/views/rooms/MessageComposerInput.js b/src/components/views/rooms/MessageComposerInput.js
index 46abc20ed6..1c81a69f16 100644
--- a/src/components/views/rooms/MessageComposerInput.js
+++ b/src/components/views/rooms/MessageComposerInput.js
@@ -503,18 +503,14 @@ export default class MessageComposerInput extends React.Component {
     }
 
     onUpArrow(e) {
-        if(this.props.onUpArrow) {
-            if(this.props.onUpArrow()) {
-                e.preventDefault();
-            }
+        if (this.props.onUpArrow && this.props.onUpArrow()) {
+            e.preventDefault();
         }
     }
 
     onDownArrow(e) {
-        if(this.props.onDownArrow) {
-            if(this.props.onDownArrow()) {
-                e.preventDefault();
-            }
+        if (this.props.onDownArrow && this.props.onDownArrow()) {
+            e.preventDefault();
         }
     }