Abstract: To improve the high-voltage flash-over characteristics of high-pressure dharge lamps (1), and especially to prevent flash-over between terminal leads emanating from the lamp bulb and extending into a lamp base (14), the lamp base which is formed with a cup-shaped opening (13) has an insert pad (18) placed therein of fibrous web, pile, fleece or mat material, made of ceramic, quartz or glass fibers. In manufacture, the fibers are compressed, thereby fitting tightly against the terminal end, typically a pinch or press seal, of the discharge lamp bulb, and thereby substantially increasing the high voltage flash-over resistance between the terminal leads and permitting hot re-ignition of the lamp, which may require pulses of between 15 to 20 kV.