diff --git a/Gemfile.lock b/Gemfile.lock
index fe9d7a2b6f927fd0e9e05f3505e9f60c81e12361..b5f9c3beca75f1f70307e05d1afc1be99621a6b8 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -655,7 +655,7 @@ GEM
     retriable (1.4.1)
     rinku (2.0.0)
     rotp (2.1.2)
-    rouge (2.0.7)
+    rouge (2.1.0)
     rqrcode (0.7.0)
       chunky_png
     rqrcode-rails3 (0.1.7)
diff --git a/lib/rouge/lexers/math.rb b/lib/rouge/lexers/math.rb
index 80784adfd76930d603e3d7f74e60e5cde2d77a8a..939b23a34212cb5dc7d70b55a86630656ba24f38 100644
--- a/lib/rouge/lexers/math.rb
+++ b/lib/rouge/lexers/math.rb
@@ -1,21 +1,9 @@
 module Rouge
   module Lexers
-    class Math < Lexer
+    class Math < PlainText
       title "A passthrough lexer used for LaTeX input"
-      desc "A boring lexer that doesn't highlight anything"
-
+      desc "PLEASE REFACTOR - this should be handled by SyntaxHighlightFilter"
       tag 'math'
-      mimetypes 'text/plain'
-
-      default_options token: 'Text'
-
-      def token
-        @token ||= Token[option :token]
-      end
-
-      def stream_tokens(string, &b)
-        yield self.token, string
-      end
     end
   end
 end
diff --git a/lib/rouge/lexers/plantuml.rb b/lib/rouge/lexers/plantuml.rb
index 7d5700b7f6dbd0b028908b78096d16011389a4e0..63c461764fc617e78eff150cc5e6035a72aa5bf9 100644
--- a/lib/rouge/lexers/plantuml.rb
+++ b/lib/rouge/lexers/plantuml.rb
@@ -1,21 +1,9 @@
 module Rouge
   module Lexers
-    class Plantuml < Lexer
+    class Plantuml < PlainText
       title "A passthrough lexer used for PlantUML input"
-      desc "A boring lexer that doesn't highlight anything"
-
+      desc "PLEASE REFACTOR - this should be handled by SyntaxHighlightFilter"
       tag 'plantuml'
-      mimetypes 'text/plain'
-
-      default_options token: 'Text'
-
-      def token
-        @token ||= Token[option :token]
-      end
-
-      def stream_tokens(string, &b)
-        yield self.token, string
-      end
     end
   end
 end