diff --git a/.config/fish/functions/brew-save.fish b/.config/fish/functions/brew-save.fish
index e5097c4..79cd9ad 100755
--- a/.config/fish/functions/brew-save.fish
+++ b/.config/fish/functions/brew-save.fish
@@ -6,10 +6,16 @@ function brew-save -d "Install a new homebrew cask and update the global Brewfil
     else
       set -f brewfile_keyword brew
     end
-    echo "$brewfile_keyword \"$package\"" >> ~/.Brewfile
-    brew bundle --global
+    set -l brewfile_line "$brewfile_keyword \"$package\""
+    if grep $brewfile_line ~/.Brewfile &> /dev/null
+      echo "package already in ~/.Brewfile: $package"
+      return 1
+    else
+      echo "$brewfile_keyword \"$package\"" >> ~/.Brewfile
+      brew bundle --global
+    end
   else
-    echo "package not found: $argv"
+    echo "package not found: $package"
     return 1
   end
 end