diff --git a/cpu/esp8266/include/periph_cpu.h b/cpu/esp8266/include/periph_cpu.h
index 2b432f6d2f..461f043efe 100644
--- a/cpu/esp8266/include/periph_cpu.h
+++ b/cpu/esp8266/include/periph_cpu.h
@@ -131,7 +131,7 @@ typedef enum {
  *
  * @{
  */
-
+#ifndef DOXYGEN
 /**
  * @brief    Override I2C clock speed values
  *
@@ -147,7 +147,7 @@ typedef enum {
     I2C_SPEED_HIGH,         /**< not supported */
 } i2c_speed_t;
 /** @} */
-
+#endif /* ndef DOXYGEN */
 /**
  * @brief   I2C configuration structure type
  */