diff --git a/db/migrate/4_add_unique_index_to_friendships.rb b/db/migrate/4_add_unique_index_to_friendships.rb
index a04279d..db36ff4 100644
--- a/db/migrate/4_add_unique_index_to_friendships.rb
+++ b/db/migrate/4_add_unique_index_to_friendships.rb
@@ -14,6 +14,8 @@ def self.up
   end
 
   def self.down
+    return unless index_exists?(:friendships, [:friendable_id, :friend_id])
+
     remove_index :friendships, [:friendable_id, :friend_id]
   end
 end