diff --git a/readthedocs/doc_builder/python_environments.py b/readthedocs/doc_builder/python_environments.py
index e117bbcca15..987067069ab 100644
--- a/readthedocs/doc_builder/python_environments.py
+++ b/readthedocs/doc_builder/python_environments.py
@@ -99,7 +99,7 @@ def install_package(self, install):
                 '-m',
                 'pip',
                 'install',
-                '--ignore-installed',
+                '--force-reinstall',
                 '--cache-dir',
                 self.project.pip_cache_path,
                 '{path}{extra_requirements}'.format(