diff --git a/package.json b/package.json
index 56449f2..ff5b0f8 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@uci/mqtt",
-  "version": "0.1.10",
+  "version": "0.1.11",
   "description": "mqtt client with json payloads and mqtt custom broker",
   "main": "src",
   "scripts": {
@@ -31,7 +31,8 @@
     "is-plain-object": "^2.0.4",
     "lodash.merge": "^4.6.1",
     "lodash.union": "^4.6.0",
-    "lodash.xor": "^4.5.0"
+    "lodash.xor": "^4.5.0",
+    "mqtt-match": "^2.0.2"
   },
   "devDependencies": {
     "chai": "^4.2.0",
diff --git a/src/client.js b/src/client.js
index fc9b478..3d1d38b 100644
--- a/src/client.js
+++ b/src/client.js
@@ -6,6 +6,7 @@ import union from 'lodash.union'
 import xor from 'lodash.xor'
 import logger from '@uci-utils/logger'
 import isPlainObject from 'is-plain-object'
+import isTopicMatch from 'mqtt-match'
 
 let log = {}
 
@@ -31,6 +32,7 @@ class MQTTClient {
       id: this.id
     })
     this.url = opts.url || null
+    this.error = opts.error || 'error' // error topic
     // subscription topics can be string of commna delimited or array of strings.  If none they by default topic is id
     this.topics = Array.isArray(opts.topics)
       ? opts.topics
@@ -154,8 +156,17 @@ class MQTTClient {
       // payload had no command that use topic as cmd
       else packet = { cmd: topic }
       let res = (await this._packetProcess(packet, topic)) || {}
-      log.debug({method:'_listen', line:159, msg:'processed packet back to broker - cmd: should NOT be a subscribed topic or infinite loop!', res:res, topics:this.topics})
-      // TODO!!!!!!!!!! make sure cmd/topic is not the same as subscribed topics or can make an infinite loop
+      log.debug({method:'_listen', line:159, msg:'processed packet back to broker', res:res, topics:this.topics})
+      if (this.topics.some(topic => isTopicMatch(topic,res.cmd))) {
+        if (this.topics.some( topic => isTopicMatch(topic,this.error))) {
+          log.warn({method:'_listen', line:165, msg:'unable to send error, subscried to error topic', subscribed:this.topics, errorTopic:this.error})
+          return
+        }
+        else {
+          res = {cmd:'error', msg:`unable to send this response, response topic '${res.cmd}'' matches a topic [${this.topics}] - subscribed to by sender`, response:res, subcribed:this.topics}
+          log.warn({method:'_listen', line:168,msg:'sent mqtt error message', error:res})
+        }
+      }
       this.send(res)
     }
   }