diff --git a/CHANGES.rst b/CHANGES.rst
index 12ccb737fd..19e5b9e681 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -4,6 +4,7 @@ Changelog
 2.2.0 (unreleased)
 ------------------
 
+- #1918 Fix stale combobox items displayed when search query changed
 - #1917 Fix wrong context in reference widget lookups
 - #1916 Provide the request record to object info adapters in the sample add form
 - #1913 Ported PR #1865 for dexterity contents
diff --git a/src/senaite/core/browser/static/js/bika.lims.analysisrequest.add.js b/src/senaite/core/browser/static/js/bika.lims.analysisrequest.add.js
index 400c69b65f..4b8158daf7 100644
--- a/src/senaite/core/browser/static/js/bika.lims.analysisrequest.add.js
+++ b/src/senaite/core/browser/static/js/bika.lims.analysisrequest.add.js
@@ -510,8 +510,7 @@
         return;
       }
       options = JSON.parse(field.attr("combogrid_options"));
-      url = this.get_base_url();
-      url += "/" + options.url;
+      url = options.url;
       url += "?_authenticator=" + (this.get_authenticator());
       url += "&catalog_name=" + catalog_name;
       url += "&colModel=" + (JSON.stringify(options.colModel));
@@ -532,7 +531,8 @@
       options.url = url;
       options.force_all = "false";
       field.combogrid(options);
-      return field.attr("search_query", "{}");
+      field.attr("search_query", "{}");
+      return field.trigger("blur");
     };
 
     AnalysisRequestAdd.prototype.set_reference_field = function(field, uid, title) {
diff --git a/src/senaite/core/browser/static/js/coffee/bika.lims.analysisrequest.add.coffee b/src/senaite/core/browser/static/js/coffee/bika.lims.analysisrequest.add.coffee
index fe2b0ce2e0..ad1236acac 100644
--- a/src/senaite/core/browser/static/js/coffee/bika.lims.analysisrequest.add.coffee
+++ b/src/senaite/core/browser/static/js/coffee/bika.lims.analysisrequest.add.coffee
@@ -491,9 +491,11 @@ class window.AnalysisRequestAdd
     # get the combogrid options
     options = JSON.parse field.attr "combogrid_options"
 
+    # we have absolute URLs now
+    # https://github.com/senaite/senaite.core/pull/1917
+    url = options.url
+
     # prepare the new query url
-    url = @get_base_url()
-    url += "/#{options.url}"
     url += "?_authenticator=#{@get_authenticator()}"
     url += "&catalog_name=#{catalog_name}"
     url += "&colModel=#{JSON.stringify options.colModel}"
@@ -519,10 +521,12 @@ class window.AnalysisRequestAdd
     options.url = url
     options.force_all = "false"
 
-
     field.combogrid options
     field.attr "search_query", "{}"
 
+    # close on any open searchbox to force reload on the next focus
+    field.trigger("blur")
+
 
   set_reference_field: (field, uid, title) =>
     ###
diff --git a/src/senaite/core/browser/widgets/referencewidget.py b/src/senaite/core/browser/widgets/referencewidget.py
index 85c4d49ce7..7c9c1d3adc 100644
--- a/src/senaite/core/browser/widgets/referencewidget.py
+++ b/src/senaite/core/browser/widgets/referencewidget.py
@@ -96,18 +96,25 @@ def process_form(self, instance, field, form, empty_marker=None,
             uid = None
         return uid, {}
 
+    def get_search_url(self, context):
+        """Prepare an absolute search url for the combobox
+        """
+        # ensure we have an absolute url for the current context
+        url = api.get_url(context)
+        # normalize portal factory urls
+        url = url.split("portal_factory")[0]
+        # ensure the search path does not contain already the url
+        search_path = self.url.split(url)[-1]
+        # return the absolute search url
+        return "/".join([url, search_path])
+
     def get_combogrid_options(self, context, fieldName):
         colModel = self.colModel
         if "UID" not in [x["columnName"] for x in colModel]:
             colModel.append({"columnName": "UID", "hidden": True})
 
-        # ensure we have an absolute url for the current context
-        url = api.get_url(context)
-        search_path = self.url.split(url)[-1]
-        search_url = "/".join([url, search_path])
-
         options = {
-            "url": search_url,
+            "url": self.get_search_url(context),
             "colModel": colModel,
             "showOn": self.showOn,
             "width": self.popup_width,
diff --git a/src/senaite/core/skins/senaite_templates/senaite_widgets/referencewidget.js b/src/senaite/core/skins/senaite_templates/senaite_widgets/referencewidget.js
index 1a1c9459f7..0ae4e343f1 100644
--- a/src/senaite/core/skins/senaite_templates/senaite_widgets/referencewidget.js
+++ b/src/senaite/core/skins/senaite_templates/senaite_widgets/referencewidget.js
@@ -133,9 +133,6 @@ function referencewidget_lookups(elements) {
       }
     };
 
-    if (window.location.href.search("portal_factory") > -1) {
-      options.url = window.location.href.split("/portal_factory")[0] + "/" + options.url;
-    }
     options.url = options.url + "?_authenticator=" + $("input[name='_authenticator']").val();
     options.url = options.url + "&catalog_name=" + $(element).attr("catalog_name");
     options.url = options.url + "&base_query=" + $(element).attr("base_query");