Requery was working now is not

[Thorson]

I created a subform that had a requery coding in the event AfterUpdate for
cboDrugName, after cboDrugName was updated it would requery
cboAdministrationRoute:
Private Sub cboDrugName_AfterUpdate()
[cboAdministrationRoute].Requery
End Sub

This was working perfectly, however, I then created another requery code
using the main form. In the AfterUpdate Event in the main form for
cboDiagnosis I had a requery coding for cboDrugName:
Private Sub cboDiagnosis_AfterUpdate()
[frmTherapeuticIndTreatmentRecords]![cboDrugName].Requery
End Sub

This new requery in the main form is working great, however for some reason
once I pull up something in the cboDrugName the requery isn't working for
cboAdministrationRoute, the query linked to cboAdministrationRoute isn't
recognizing that their is anything in cboDrugName. This is the SQL for
qryDrugList (this is the query linked to cboAdministrationRoute).

SELECT tblDrugList.DrugName, tblDrugList.AdministrationRoute.Value
FROM tblDrugList
WHERE
(((tblDrugList.DrugName)=[Forms]![frmTherapeuticIndTreatmentRecords]![cboDrugName]));