diff --git a/Library/Homebrew/cmd/doctor.rb b/Library/Homebrew/cmd/doctor.rb
index 39fed18d92..36073daf32 100644
--- a/Library/Homebrew/cmd/doctor.rb
+++ b/Library/Homebrew/cmd/doctor.rb
@@ -533,8 +533,11 @@ def check_for_config_scripts
 
   config_scripts = []
 
+  whitelist = %W[/usr/bin /usr/sbin /usr/X11/bin /usr/X11R6/bin /opt/X11/bin #{HOMEBREW_PREFIX}/bin #{HOMEBREW_PREFIX}/sbin]
+  whitelist.map! { |d| d.downcase }
+
   path_folders.each do |p|
-    next if ['/usr/bin', '/usr/sbin', '/usr/X11/bin', '/usr/X11R6/bin', "#{HOMEBREW_PREFIX}/bin", "#{HOMEBREW_PREFIX}/sbin", "/opt/X11/bin"].include? p
+    next if whitelist.include? p.downcase
     next if p =~ %r[^(#{real_cellar.to_s}|#{HOMEBREW_CELLAR.to_s})] if real_cellar
 
     configs = Dir["#{p}/*-config"]