diff --git a/Library/Homebrew/install.rb b/Library/Homebrew/install.rb
index 48b9acb362..c0f04eb3ba 100644
--- a/Library/Homebrew/install.rb
+++ b/Library/Homebrew/install.rb
@@ -469,7 +469,7 @@ module Homebrew
           end.flat_map(&:to_formula)]
         end.flatten.uniq
         formulae_dependencies.concat(dependants.upgradeable) if dependants&.upgradeable
-        formulae_dependencies
+        formulae_dependencies.uniq
       end
     end
   end