Index: sources/gui/qml/components/HeaderBar.qml
===================================================================
diff -u -r40ddf63592b60608ae34aeb3099fe4e62ae45054 -r9ea6aa3bf4e8c4b5ef8970a6c19ad12b5765c58d
--- sources/gui/qml/components/HeaderBar.qml	(.../HeaderBar.qml)	(revision 40ddf63592b60608ae34aeb3099fe4e62ae45054)
+++ sources/gui/qml/components/HeaderBar.qml	(.../HeaderBar.qml)	(revision 9ea6aa3bf4e8c4b5ef8970a6c19ad12b5765c58d)
@@ -114,6 +114,10 @@
             iconSize        : Variables.headerIconDiameter
             iconImageSource : "qrc:/images/iPrescription"
             extraSpace      : _headerButtonRow.spacing
+            visible         : vTDOpMode.validateParameters  ||
+                              vTDOpMode.preTreatment        ||
+                              vTDOpMode.inTreatment         ||
+                              vTDOpMode.postTreatment
 
             onPressed       : _headerbarPrescription.open()
         }