Item name disappears when you edit / select an item on a transaction - Here's a workaround.

From NetSuite Wiki

You may have noticed that upon selecting a previously entered item, the item name (on the left) disappears. Thus, if you click "Add" the item disappears. This problem is intermittent, and may affect certain browser versions more than others.Workaround: If you highlight text in any of the fields of the item row in question, rather than just clicking on it, the problem never occurs.This problem occurs in all transactions Sales Orders, Invoices, Cash Sales, Return Authorizations also in Item Records under Related Items and Categories.Observed in Slimbrowser and Internet Explorer.