diff --git a/R/kable_styling.R b/R/kable_styling.R
index bbb8e07..d349120 100644
--- a/R/kable_styling.R
+++ b/R/kable_styling.R
@@ -169,7 +169,7 @@
 
   out <- as_kable_xml(kable_xml)
   attributes(out) <- kable_attrs
-  class(out) <- c("kableExtra", class(out))
+  if (!"kableExtra" %in% class(out)) class(out) <- c("kableExtra", class(out))
   return(out)
 }