diff --git a/drivers/I2CSlave.h b/drivers/I2CSlave.h
index 59f7d3760f..1c85b573da 100644
--- a/drivers/I2CSlave.h
+++ b/drivers/I2CSlave.h
@@ -150,8 +150,13 @@ public:
      */
     void stop(void);
 
+#if !defined(DOXYGEN_ONLY)
+
 protected:
+    /* Internal i2c object identifying the resources */
     i2c_t _i2c;
+
+#endif //!defined(DOXYGEN_ONLY)
 };
 
 } // namespace mbed