Once you create a trigger, it remains in the database until someone explicitly removes it. You must have ALTER permissions on the table associated with the trigger to drop the trigger.
Open the Triggers folder.
Right-click the desired trigger and choose Delete from the popup menu.
Connect to a database.
Execute a DROP TRIGGER statement.
The following statement removes the trigger mytrigger from the database:
DROP TRIGGER mytrigger;
For more information, see DROP statement.