diff --git a/include/mbedtls/hmac_drbg.h b/include/mbedtls/hmac_drbg.h
index e010558..e3e1942 100644
--- a/include/mbedtls/hmac_drbg.h
+++ b/include/mbedtls/hmac_drbg.h
@@ -26,7 +26,7 @@
 #include "md.h"
 
 #if defined(MBEDTLS_THREADING_C)
-#include "mbedtls/threading.h"
+#include "threading.h"
 #endif
 
 /*