diff --git a/src/connection.js b/src/connection.js
index 578a6a02..97cc97e1 100644
--- a/src/connection.js
+++ b/src/connection.js
@@ -385,7 +385,7 @@ function Connection(options, queues = {}, { onopen = noop, onend = noop, onclose
   }
 
   function queryError(query, err) {
-    Object.defineProperties(err, {
+    'query' in err || 'parameters' in err || Object.defineProperties(err, {
       stack: { value: err.stack + query.origin.replace(/.*\n/, '\n'), enumerable: options.debug },
       query: { value: query.string, enumerable: options.debug },
       parameters: { value: query.parameters, enumerable: options.debug },