diff --git a/rdkit/Chem/PandasTools.py b/rdkit/Chem/PandasTools.py
index a3065c573..cebf3d428 100644
--- a/rdkit/Chem/PandasTools.py
+++ b/rdkit/Chem/PandasTools.py
@@ -197,19 +197,19 @@ def patchPandasrepr(self, **kwargs):
   global defPandasGetAdjustment
 
   import pandas.io.formats.html
-  if not hasattr(pandas.io.formats.html.HTMLFormatter, "_rdkitpatched"):
-    defHTMLFormatter_write_cell = pd.io.formats.html.HTMLFormatter._write_cell
-    pd.io.formats.html.HTMLFormatter._write_cell = _patched_HTMLFormatter_write_cell
-    pandas.io.formats.html.HTMLFormatter._rdkitpatched = True
-  get_adjustment_attr = getAdjustmentAttr()
-  if get_adjustment_attr:
-    defPandasGetAdjustment = getattr(pd.io.formats.format, get_adjustment_attr)
-    setattr(pd.io.formats.format, get_adjustment_attr, _patched_get_adjustment)
-  res = defPandasRepr(self, **kwargs)
-  if get_adjustment_attr:
-    setattr(pd.io.formats.format, get_adjustment_attr, defPandasGetAdjustment)
-  pd.io.formats.html.HTMLFormatter._write_cell = defHTMLFormatter_write_cell
-  return res
+  defHTMLFormatter_write_cell = pd.io.formats.html.HTMLFormatter._write_cell
+  pd.io.formats.html.HTMLFormatter._write_cell = _patched_HTMLFormatter_write_cell
+  try:
+    get_adjustment_attr = getAdjustmentAttr()
+    if get_adjustment_attr:
+      defPandasGetAdjustment = getattr(pd.io.formats.format, get_adjustment_attr)
+      setattr(pd.io.formats.format, get_adjustment_attr, _patched_get_adjustment)
+    res = defPandasRepr(self, **kwargs)
+    if get_adjustment_attr:
+      setattr(pd.io.formats.format, get_adjustment_attr, defPandasGetAdjustment)
+    return res
+  finally:
+    pd.io.formats.html.HTMLFormatter._write_cell = defHTMLFormatter_write_cell
 
 
 def patchPandasHTMLrepr(self, **kwargs):