diff --git a/sys/include/net/gnrc/sixlowpan/config.h b/sys/include/net/gnrc/sixlowpan/config.h
index 5401d3afd7..0388313a33 100644
--- a/sys/include/net/gnrc/sixlowpan/config.h
+++ b/sys/include/net/gnrc/sixlowpan/config.h
@@ -132,8 +132,8 @@ extern "C" {
  * immediately. Use this value to prevent re-creation of a reassembly buffer
  * entry on late arriving link-layer duplicates.
  */
-#ifndef GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER
-#define GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER              (0U)
+#ifndef CONFIG_GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER
+#define CONFIG_GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER              (0U)
 #endif
 
 /**
diff --git a/sys/net/gnrc/network_layer/sixlowpan/frag/rb/gnrc_sixlowpan_frag_rb.c b/sys/net/gnrc/network_layer/sixlowpan/frag/rb/gnrc_sixlowpan_frag_rb.c
index 59af193f5d..c4cd26d8ee 100644
--- a/sys/net/gnrc/network_layer/sixlowpan/frag/rb/gnrc_sixlowpan_frag_rb.c
+++ b/sys/net/gnrc/network_layer/sixlowpan/frag/rb/gnrc_sixlowpan_frag_rb.c
@@ -364,7 +364,7 @@ static bool _rbuf_update_ints(gnrc_sixlowpan_frag_rb_base_t *entry,
 
 static void _gc_pkt(gnrc_sixlowpan_frag_rb_t *rbuf)
 {
-#if GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER > 0
+#if CONFIG_GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER > 0
     if (rbuf->super.current_size == 0) {
         /* packet is scheduled for deletion, but was complete, i.e. pkt is
          * already handed up to other layer, i.e. no need to release */
@@ -433,7 +433,7 @@ static int _rbuf_get(const void *src, size_t src_len,
                                          rbuf[i].super.dst_len,
                                          l2addr_str),
                   (unsigned)rbuf[i].super.datagram_size, rbuf[i].super.tag);
-#if GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER > 0
+#if CONFIG_GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER > 0
             if (rbuf[i].super.current_size == 0) {
                 /* ensure that only empty reassembly buffer entries and entries
                  * scheduled for deletion have `current_size == 0` */
@@ -563,21 +563,21 @@ void gnrc_sixlowpan_frag_rb_base_rm(gnrc_sixlowpan_frag_rb_base_t *entry)
 
 static void _tmp_rm(gnrc_sixlowpan_frag_rb_t *rbuf)
 {
-#if GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER > 0U
+#if CONFIG_GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER > 0U
         /* use garbage-collection to leave the entry for at least
-         * GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER in the reassembly buffer by
+         * CONFIG_GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER in the reassembly buffer by
          * setting the arrival time to
-         * (CONFIG_GNRC_SIXLOWPAN_FRAG_RBUF_TIMEOUT_US - GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER)
+         * (CONFIG_GNRC_SIXLOWPAN_FRAG_RBUF_TIMEOUT_US - CONFIG_GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER)
          * microseconds in the past */
         rbuf->super.arrival = xtimer_now_usec() -
                               (CONFIG_GNRC_SIXLOWPAN_FRAG_RBUF_TIMEOUT_US -
-                               GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER);
+                               CONFIG_GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER);
         /* reset current size to prevent late duplicates to trigger another
          * dispatch */
         rbuf->super.current_size = 0;
-#else   /* GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER == 0U */
+#else   /* CONFIG_GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER == 0U */
         gnrc_sixlowpan_frag_rb_remove(rbuf);
-#endif  /* GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER */
+#endif  /* CONFIG_GNRC_SIXLOWPAN_FRAG_RBUF_DEL_TIMER */
 }
 
 int gnrc_sixlowpan_frag_rb_dispatch_when_complete(gnrc_sixlowpan_frag_rb_t *rbuf,