Depends on whether the dropdown came from the 'Forms' toolbar or the 'Control Toolbox'.

Also on whether you're wanting to control the information shown in the dropdowns in code or from a worksheet selection.

1. IN CODE:

If from 'Forms', you would use the code
Worksheets("Sheetname").Dropdowns("Dropdownname"). RemoveItem(number of item to delete)

If from 'Control Toolbox', you would use the code
Sheetname.Dropdownname.RemoveItem(number of item to delete-1)
- i.e. the top item is Item No. 0 (zero).


2. AS WORKSHEET SELECTIONS:

If from 'Forms',
- right-click on the dropdown box and select 'Format Control'
- check the address/range entered as the 'Input Range' and modify as necessary to include the additional rows or remove the redundant rows

If from 'Control Toolbox',
- right-click on the dropdown box and select 'Properties'
- a VBA-style property window appears, floating on the worksheet.
- check the address/range entered as the 'ListFillRange' property and modify as necessary.


Hope this helps.

Regards,
BizMark