diff --git a/src/pipx/commands/list_packages.py b/src/pipx/commands/list_packages.py
index 1b72631..d7bc211 100644
--- a/src/pipx/commands/list_packages.py
+++ b/src/pipx/commands/list_packages.py
@@ -30,14 +30,21 @@ def list_text(
     print(f"venvs are in {bold(venv_root_dir)}")
     print(f"apps are exposed on your $PATH at {bold(str(constants.LOCAL_BIN_DIR))}")
 
+    warning_messages = []
     all_venv_problems = VenvProblems()
     for venv_dir in venv_dirs:
         package_summary, venv_problems = get_venv_summary(
             venv_dir, include_injected=include_injected
         )
-        print(package_summary)
+        if venv_problems.any_():
+            warning_messages.append(package_summary)
+        else:
+            print(package_summary)
         all_venv_problems.or_(venv_problems)
 
+    for warning_message in warning_messages:
+        print(warning_message, file=sys.stderr)
+
     return all_venv_problems
 
 
@@ -75,7 +82,7 @@ def list_packages(
     """Returns pipx exit code."""
     venv_dirs: Collection[Path] = sorted(venv_container.iter_venv_dirs())
     if not venv_dirs:
-        print(f"nothing has been installed with pipx {sleep}")
+        print(f"nothing has been installed with pipx {sleep}", file=sys.stderr)
         return EXIT_CODE_OK
 
     venv_container.verify_shared_libs()
@@ -89,27 +96,31 @@ def list_packages(
         print(
             "\nOne or more packages contain out-of-date internal data installed from a\n"
             "previous pipx version and need to be updated.\n"
-            "    To fix, execute: pipx reinstall-all"
+            "    To fix, execute: pipx reinstall-all",
+            file=sys.stderr,
         )
     if all_venv_problems.invalid_interpreter:
         print(
             "\nOne or more packages have a missing python interpreter.\n"
-            "    To fix, execute: pipx reinstall-all"
+            "    To fix, execute: pipx reinstall-all",
+            file=sys.stderr,
         )
     if all_venv_problems.missing_metadata:
         print(
             "\nOne or more packages have a missing internal pipx metadata.\n"
             "   They were likely installed using a pipx version before 0.15.0.0.\n"
-            "   Please uninstall and install these package(s) to fix."
+            "   Please uninstall and install these package(s) to fix.",
+            file=sys.stderr,
         )
     if all_venv_problems.not_installed:
         print(
             "\nOne or more packages are not installed properly.\n"
-            "   Please uninstall and install these package(s) to fix."
+            "   Please uninstall and install these package(s) to fix.",
+            file=sys.stderr,
         )
 
     if all_venv_problems.any_():
-        print()
+        print(file=sys.stderr)
         return EXIT_CODE_LIST_PROBLEM
 
     return EXIT_CODE_OK