diff --git a/CHANGES b/CHANGES
index e978290..0f65aad 100644
--- a/CHANGES
+++ b/CHANGES
@@ -5,6 +5,7 @@ pint-pandas Changelog
 ----------------
 
 - Support for uncertainties as magnitudes in PintArrays. #140
+- Fix dequantify duplicate column failure #202
 - Fix astype issue #196
 
 0.5 (2023-09-07)
diff --git a/docs/getting/index.rst b/docs/getting/index.rst
index da8a44a..6e000fc 100644
--- a/docs/getting/index.rst
+++ b/docs/getting/index.rst
@@ -7,7 +7,7 @@ The getting started guide aims to get you using pint-pandas productively as quic
 What is Pint-pandas?
 --------------------
 
-The Pandas package provides powerful DataFrame and Series abstractions for dealing with numerical, temporal, categorical, string-based, and even user-defined data (using its ExtensionArray feature). The Pint package provides a rich and extensible vocabulary of units for constructing Quantities and an equally rich and extensible range of unit conversions to make it easy to perform unit-safe calculations using Quantities. Pint-pandas provides PintArray, aPandas ExtensionArray that efficiently implements Pandas DataFrame and Series functionality as unit-aware operations where appropriate.
+The Pandas package provides powerful DataFrame and Series abstractions for dealing with numerical, temporal, categorical, string-based, and even user-defined data (using its ExtensionArray feature). The Pint package provides a rich and extensible vocabulary of units for constructing Quantities and an equally rich and extensible range of unit conversions to make it easy to perform unit-safe calculations using Quantities. Pint-pandas provides PintArray, a Pandas ExtensionArray that efficiently implements Pandas DataFrame and Series functionality as unit-aware operations where appropriate.
 
 Those who have used Pint know well that good units discipline often catches not only simple mistakes, but sometimes more fundamental errors as well. Pint-pandas can reveal similar errors when it comes to slicing and dicing Pandas data.
 
diff --git a/pint_pandas/pint_array.py b/pint_pandas/pint_array.py
index c5b927f..138bb7f 100644
--- a/pint_pandas/pint_array.py
+++ b/pint_pandas/pint_array.py
@@ -1,7 +1,6 @@
 import copy
 import re
 import warnings
-from collections import OrderedDict
 from importlib.metadata import version
 
 import numpy as np
@@ -1082,23 +1081,35 @@ def formatter_func(dtype):
 
         df_columns = df.columns.to_frame()
         df_columns["units"] = [
-            formatter_func(df[col].dtype)
-            if isinstance(df[col].dtype, PintType)
+            formatter_func(df.dtypes.iloc[i])
+            if isinstance(df.dtypes.iloc[i], PintType)
             else NO_UNIT
-            for col in df.columns
+            for i, col in enumerate(df.columns)
         ]
 
-        data_for_df = OrderedDict()
+        data_for_df = []
         for i, col in enumerate(df.columns):
-            if isinstance(df[col].dtype, PintType):
-                data_for_df[tuple(df_columns.iloc[i])] = df[col].values.data
+            if isinstance(df.dtypes.iloc[i], PintType):
+                data_for_df.append(
+                    pd.Series(
+                        data=df.iloc[:, i].values.data,
+                        name=tuple(df_columns.iloc[i]),
+                        index=df.index,
+                        copy=False,
+                    )
+                )
             else:
-                data_for_df[tuple(df_columns.iloc[i])] = df[col].values
-
-        df_new = DataFrame(data_for_df, columns=data_for_df.keys())
+                data_for_df.append(
+                    pd.Series(
+                        data=df.iloc[:, i].values,
+                        name=tuple(df_columns.iloc[i]),
+                        index=df.index,
+                        copy=False,
+                    )
+                )
 
+        df_new = pd.concat(data_for_df, axis=1, copy=False)
         df_new.columns.names = df.columns.names + ["unit"]
-        df_new.index = df.index
 
         return df_new
 
diff --git a/pint_pandas/testsuite/test_issues.py b/pint_pandas/testsuite/test_issues.py
index 0e606d2..1bd9229 100644
--- a/pint_pandas/testsuite/test_issues.py
+++ b/pint_pandas/testsuite/test_issues.py
@@ -245,3 +245,38 @@ def test_issue_194(dtype):
     s2 = s1.astype(dtype)
 
     tm.assert_series_equal(s0, s2)
+
+
+class TestIssue202(BaseExtensionTests):
+    def test_dequantify(self):
+        df = pd.DataFrame()
+        df["test"] = pd.Series([1, 2, 3], dtype="pint[kN]")
+        df.insert(0, "test", df["test"], allow_duplicates=True)
+
+        expected = pd.DataFrame.from_dict(
+            data={
+                "index": [0, 1, 2],
+                "columns": [("test", "kilonewton")],
+                "data": [[1], [2], [3]],
+                "index_names": [None],
+                "column_names": [None, "unit"],
+            },
+            orient="tight",
+            dtype="Int64",
+        )
+        result = df.iloc[:, 1:].pint.dequantify()
+        tm.assert_frame_equal(expected, result)
+
+        expected = pd.DataFrame.from_dict(
+            data={
+                "index": [0, 1, 2],
+                "columns": [("test", "kilonewton"), ("test", "kilonewton")],
+                "data": [[1, 1], [2, 2], [3, 3]],
+                "index_names": [None],
+                "column_names": [None, "unit"],
+            },
+            orient="tight",
+            dtype="Int64",
+        )
+        result = df.pint.dequantify()
+        tm.assert_frame_equal(expected, result)