diff --git a/include/polarssl/hmac_drbg.h b/include/polarssl/hmac_drbg.h
index 36d1200..79be0a6 100644
--- a/include/polarssl/hmac_drbg.h
+++ b/include/polarssl/hmac_drbg.h
@@ -37,10 +37,12 @@
 #define POLARSSL_ERR_HMAC_DRBG_INPUT_TOO_BIG                -0x0038  /**< Input too large (Entropy + additional). */
 #define POLARSSL_ERR_HMAC_DRBG_FILE_IO_ERROR                -0x003A  /**< Read/write error in file. */
 
+#if !defined(POLARSSL_CONFIG_OPTIONS)
 #define POLARSSL_HMAC_DRBG_RESEED_INTERVAL   10000   /**< Interval before reseed is performed by default */
 #define POLARSSL_HMAC_DRBG_MAX_INPUT         256     /**< Maximum number of additional input bytes */
 #define POLARSSL_HMAC_DRBG_MAX_REQUEST       1024    /**< Maximum number of requested bytes per call */
 #define POLARSSL_HMAC_DRBG_MAX_SEED_INPUT    384     /**< Maximum size of (re)seed buffer */
+#endif /* !POLARSSL_CONFIG_OPTIONS */
 
 #define POLARSSL_HMAC_DRBG_PR_OFF   0   /**< No prediction resistance       */
 #define POLARSSL_HMAC_DRBG_PR_ON    1   /**< Prediction resistance enabled  */