Very early international flight out of IAH. What time should we arrive?

Fiancé and I are going on an international flight that is set to leave at 6:00 am on a Friday. Should we ACTUALLY arrive at 4:00 am? I’ve only ever flown domestic out of IAH, HOU I’ve never had this early of a flight so I’ve always shown up the two hours early just in case. I’d hate to leave the house at 3:30 am and get through security in 20 minutes. Anyone have any experience with this early of an international flight?