diff --git a/lib/database/accounts.js b/lib/database/accounts.js
index f270e5d7..5128e858 100644
--- a/lib/database/accounts.js
+++ b/lib/database/accounts.js
@@ -13,7 +13,7 @@ var blackHole = function () { };
  * visually identical to existing names in certain fonts.
  */
 function wildcardSimilarChars(name) {
-    return name.replace(/[Il1oO0]/g, "_");
+    return name.replace(/_/g, "\\_").replace(/[Il1oO0]/g, "_");
 }
 
 module.exports = {
@@ -24,7 +24,8 @@ module.exports = {
      * Check if a username is taken
      */
     isUsernameTaken: function (name, callback) {
-        db.query("SELECT name FROM `users` WHERE name LIKE ?", [wildcardSimilarChars(name)],
+        db.query("SELECT name FROM `users` WHERE name LIKE ? ESCAPE '\\\\'",
+                 [wildcardSimilarChars(name)],
         function (err, rows) {
             if (err) {
                 callback(err, true);