As a default, all item codes are shown in invoices. However, item codes can be removed from patient invoices.
This will mainly be for item codes that are not accountable and/or treatment i.e. NOTES
Go to Location Setup > Items tab
Select an item and select the Financial Details sub-tab
Remove the tick from Show in Invoices
If the tick is removed from this box, the item code will not show in the Fees tab either.