diff --git a/app/services/flavored_markdown.rb b/app/services/flavored_markdown.rb
index e88f0453..a356d07e 100644
--- a/app/services/flavored_markdown.rb
+++ b/app/services/flavored_markdown.rb
@@ -6,7 +6,7 @@ class FlavoredMarkdown < Redcarpet::Render::HTML
   end
 
   def wrap_mentions(text)
-    text.gsub! /(^|\s)(@\w+)/ do
+    text.gsub! /(^|\s)(@[a-zA-Z0-9_]{1,16})/ do
       "#{$1}[#{$2}](#{show_user_profile_path $2.tr('@', '')})"
     end
     text
@@ -23,4 +23,4 @@ class FlavoredMarkdown < Redcarpet::Render::HTML
   def raw_html(raw_html)
     Rack::Utils.escape_html raw_html
   end
-end
\ No newline at end of file
+end