diff --git a/intake_google_analytics/source.py b/intake_google_analytics/source.py
index 608a8db..46cd539 100644
--- a/intake_google_analytics/source.py
+++ b/intake_google_analytics/source.py
@@ -73,7 +73,7 @@ def _get_schema(self):
             )
 
         return Schema(datashape=None,
-                      dtype=self._df.dtypes,
+                      dtype={k: str(v) for k,v in self._df.dtypes.items()},
                       shape=(None, len(self._df.columns)),
                       npartitions=1,
                       extra_metadata={})