diff --git a/napari_plugin_manager/_tests/test_qt_plugin_dialog.py b/napari_plugin_manager/_tests/test_qt_plugin_dialog.py
index 08071616..3c1a8865 100644
--- a/napari_plugin_manager/_tests/test_qt_plugin_dialog.py
+++ b/napari_plugin_manager/_tests/test_qt_plugin_dialog.py
@@ -12,6 +12,7 @@
 from napari.utils.translations import trans
 from qtpy.QtCore import QMimeData, QPointF, Qt, QUrl
 from qtpy.QtGui import QDropEvent
+from qtpy.QtWidgets import QMessageBox
 
 if qtpy.API_NAME == 'PySide2' and sys.version_info[:2] > (3, 10):
     pytest.skip(
@@ -484,6 +485,35 @@ def test_installs(qtbot, tmp_virtualenv, plugin_dialog, request):
     qtbot.wait(5000)
 
 
+@pytest.mark.parametrize(
+    "message_return",
+    [QMessageBox.StandardButton.Cancel, QMessageBox.StandardButton.Ok],
+)
+def test_install_pypi_constructor(
+    qtbot, tmp_virtualenv, plugin_dialog, request, message_return
+):
+    if "no-constructor" in request.node.name:
+        pytest.skip(
+            reason="This test is only relevant for constructor-based installs"
+        )
+
+    plugin_dialog.set_prefix(str(tmp_virtualenv))
+    plugin_dialog.search('requests')
+    qtbot.wait(500)
+    item = plugin_dialog.available_list.item(0)
+    widget = plugin_dialog.available_list.itemWidget(item)
+    with patch.object(qt_plugin_dialog.QMessageBox, "exec_") as mock:
+        mock.return_value = message_return
+        if message_return == QMessageBox.StandardButton.Ok:
+            with qtbot.waitSignal(
+                plugin_dialog.installer.processFinished, timeout=60_000
+            ):
+                widget.action_button.click()
+        else:
+            widget.action_button.click()
+        assert mock.called
+
+
 def test_cancel(qtbot, tmp_virtualenv, plugin_dialog, request):
     if "[constructor]" in request.node.name:
         pytest.skip(
diff --git a/napari_plugin_manager/base_qt_plugin_dialog.py b/napari_plugin_manager/base_qt_plugin_dialog.py
index 816eab81..7b9b09c8 100644
--- a/napari_plugin_manager/base_qt_plugin_dialog.py
+++ b/napari_plugin_manager/base_qt_plugin_dialog.py
@@ -600,6 +600,20 @@ def _on_enabled_checkbox(self, state: Qt.CheckState) -> None:
         """
         raise NotImplementedError
 
+    def _action_validation(self, tool, action) -> bool:
+        """
+        Validate if the current action should be done or not.
+
+        As an example you could warn that a package from PyPI is going
+        to be installed.
+
+        Returns
+        -------
+        This should return a `bool`, `True` if the action should proceed, `False`
+        otherwise.
+        """
+        raise NotImplementedError
+
     def _cancel_requested(self):
         version = self.version_choice_dropdown.currentText()
         tool = self.get_installer_tool()
@@ -615,7 +629,10 @@ def _action_requested(self):
             if self.action_button.objectName() == 'install_button'
             else InstallerActions.UNINSTALL
         )
-        self.actionRequested.emit(self.item, self.name, action, version, tool)
+        if self._action_validation(tool, action):
+            self.actionRequested.emit(
+                self.item, self.name, action, version, tool
+            )
 
     def _update_requested(self):
         version = self.version_choice_dropdown.currentText()
diff --git a/napari_plugin_manager/qt_plugin_dialog.py b/napari_plugin_manager/qt_plugin_dialog.py
index f1f04371..9b5dd795 100644
--- a/napari_plugin_manager/qt_plugin_dialog.py
+++ b/napari_plugin_manager/qt_plugin_dialog.py
@@ -19,6 +19,7 @@
 from qtpy.QtGui import (
     QMovie,
 )
+from qtpy.QtWidgets import QCheckBox, QMessageBox
 
 from napari_plugin_manager.base_qt_plugin_dialog import (
     BasePluginListItem,
@@ -32,10 +33,13 @@
 )
 from napari_plugin_manager.qt_package_installer import (
     InstallerActions,
+    InstallerTools,
 )
+from napari_plugin_manager.utils import is_conda_package
 
 # Scaling factor for each list widget item when expanding.
 STYLES_PATH = Path(__file__).parent / 'styles.qss'
+DISMISS_WARN_PYPI_INSTALL_DLG = False
 
 
 def _show_message(widget):
@@ -127,6 +131,48 @@ def _on_enabled_checkbox(self, state: int):
                 )
                 return
 
+    def _warn_pypi_install(self):
+        return running_as_constructor_app() or is_conda_package(
+            'napari'
+        )  # or True
+
+    def _action_validation(self, tool, action):
+        global DISMISS_WARN_PYPI_INSTALL_DLG
+        if (
+            tool == InstallerTools.PIP
+            and action == InstallerActions.INSTALL
+            and self._warn_pypi_install()
+            and not DISMISS_WARN_PYPI_INSTALL_DLG
+        ):
+            warn_msgbox = QMessageBox(self)
+            warn_msgbox.setWindowTitle(
+                self._trans('PyPI installation on bundle/conda')
+            )
+            warn_msgbox.setText(
+                self._trans(
+                    'Installing from PyPI does not take into account existing installed packages, '
+                    'so it can break existing installations. '
+                    'If this happens the only solution is to reinstall the bundle/create a new conda environment.\n\n'
+                    'Are you sure you want to install from PyPI?'
+                )
+            )
+            warn_checkbox = QCheckBox(
+                self._trans(
+                    "Don't show this message again in the current session"
+                )
+            )
+            warn_msgbox.setCheckBox(warn_checkbox)
+            warn_msgbox.setIcon(QMessageBox.Icon.Warning)
+            warn_msgbox.setStandardButtons(
+                QMessageBox.StandardButton.Ok
+                | QMessageBox.StandardButton.Cancel
+            )
+            button_clicked = warn_msgbox.exec_()
+            DISMISS_WARN_PYPI_INSTALL_DLG = warn_checkbox.isChecked()
+            if button_clicked != QMessageBox.StandardButton.Ok:
+                return False
+        return True
+
 
 class QPluginList(BaseQPluginList):