diff --git a/src/include/ipxe/udp.h b/src/include/ipxe/udp.h
index ed049476..5717ef21 100644
--- a/src/include/ipxe/udp.h
+++ b/src/include/ipxe/udp.h
@@ -23,9 +23,6 @@ struct sockaddr;
  * UDP constants
  */
 
-#define UDP_MAX_TXIOB	ETH_MAX_MTU
-#define UDP_MIN_TXIOB	ETH_ZLEN
-
 /**
  * A UDP header
  */