diff --git a/src/Illuminate/Database/Query/Builder.php b/src/Illuminate/Database/Query/Builder.php
index 623ba961289c..bdd3a033c43b 100755
--- a/src/Illuminate/Database/Query/Builder.php
+++ b/src/Illuminate/Database/Query/Builder.php
@@ -1846,6 +1846,10 @@ public function update(array $values)
      */
     public function increment($column, $amount = 1, array $extra = [])
     {
+        if (! is_numeric($amount)) {
+            throw new InvalidArgumentException("Non-numeric value passed to increment method.");
+        }
+
         $wrapped = $this->grammar->wrap($column);
 
         $columns = array_merge([$column => $this->raw("$wrapped + $amount")], $extra);
@@ -1863,6 +1867,10 @@ public function increment($column, $amount = 1, array $extra = [])
      */
     public function decrement($column, $amount = 1, array $extra = [])
     {
+        if (! is_numeric($amount)) {
+            throw new InvalidArgumentException("Non-numeric value passed to decrement method.");
+        }
+
         $wrapped = $this->grammar->wrap($column);
 
         $columns = array_merge([$column => $this->raw("$wrapped - $amount")], $extra);