diff --git a/lib/pure/asyncdispatch.nim b/lib/pure/asyncdispatch.nim
index b3a26f303c..9f8ac014a8 100644
--- a/lib/pure/asyncdispatch.nim
+++ b/lib/pure/asyncdispatch.nim
@@ -1700,7 +1700,7 @@ proc drain*(timeout = 500) =
   let start = getMonoTime()
   while hasPendingOperations():
     discard runOnce(timeout - elapsed)
-    elapsed = (getMonoTime() - start).inMilliseconds
+    elapsed = int (getMonoTime() - start).inMilliseconds
     if elapsed >= timeout:
       break